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How to get rid of mysterious window outline?

Hiya!


Macbook pro 2009. Yesterday I started seeing a blank white box show up upon startup after cpu cycles through start up routine. Window turns transparent except for shadow box of outline after completes startup sequence. Tried to "catch" the culprit via activity monitor...no joy. When I go to minimize all existing windows (f11), that darn box moves along with all the others leading me to think it is a program or script of some sort. I just don't know how to find or fix. VERY open to suggestions 🙂


User uploaded file

MacBook Pro (15-inch Mid 2009), OS X El Capitan (10.11.2)

Posted on Dec 19, 2015 11:22 AM

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10 replies

Dec 19, 2015 3:00 PM in response to shane785300

One of your login items may be causing the problem. Please select the Login Items tab in the Users & Groups pane of System Preferences. Delete any items that you don't recognize. If you're not sure which ones to delete, double-click each to test it.

If a login item is grayed out and can't be deleted, click the padlock icon in the lower left corner of the window and enter your login password when prompted. Then try again.

To avoid confusion, note that checking or unchecking the box next to a login item does not inactivate it. You have to delete the item from the list.

Dec 19, 2015 8:52 PM in response to shane785300

Please read this whole message before doing anything.

This procedure is a test, not a solution. Don’t be disappointed when you find that nothing has changed after you complete it.

Step 1

The purpose of this step is to determine whether the problem is localized to your user account.

Enable guest logins* and log in as Guest. Don't use the Safari-only “Guest User” login created by “Find My Mac.”

While logged in as Guest, you won’t have access to any of your documents or settings. Applications will behave as if you were running them for the first time. Don’t be alarmed by this behavior; it’s normal. If you need any passwords or other personal data in order to complete the test, memorize, print, or write them down before you begin.

Test while logged in as Guest. Same problem?

After testing, log out of the guest account and, in your own account, disable it if you wish. Any files you created in the guest account will be deleted automatically when you log out of it.

*Note: If you’ve activated “Find My Mac” or FileVault, then you can’t enable the Guest account. The “Guest User” login created by “Find My Mac” is not the same. Create a new account in which to test, and delete it, including its home folder, after testing.

Step 2

The purpose of this step is to determine whether the problem is caused by third-party system modifications that load automatically at startup or login, by a peripheral device, by a font conflict, or by corruption of the file system or of certain system caches.

Please take this step regardless of the results of Step 1.

Disconnect all wired peripherals except those needed for the test, and remove all aftermarket expansion cards, if applicable. Start up in safe mode and log in to the account with the problem.

Note: If FileVault is enabled in OS X 10.9 or earlier, or if a firmware password is set, or if the startup volume is a software RAID, you can’t do this. Ask for further instructions.

Safe mode is much slower to start up and run than normal, with limited graphics performance, and some things won’t work at all, including sound output and Wi-Fi on certain models. The next normal startup may also be somewhat slow.

The login screen appears even if you usually log in automatically. You must know your login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.

Test while in safe mode. Same problem?

After testing, restart as usual (not in safe mode) and verify that you still have the problem. Post the results of Steps 1 and 2.

Dec 20, 2015 10:45 AM in response to shane785300

1. This procedure is a diagnostic test. It changes nothing, for better or worse, and therefore will not, in itself, solve the problem. But with the aid of the test results, the solution may take a few minutes, instead of hours or days.

The test works on OS X 10.7 ("Lion") and later. I don't recommend running it on older versions of OS X. It will do no harm, but it won't do much good either.

Don't be put off by the complexity of these instructions. The process is much less complicated than the description. You do harder tasks with the computer all the time.

2. If you don't already have a current backup, please back up all data before doing anything else. The backup is necessary on general principle, not because of anything in the test procedure. Backup is always a must, and when you're having any kind of trouble with the computer, you may be at higher than usual risk of losing data, whether you follow these instructions or not.

There are ways to back up a computer that isn't fully functional. Ask if you need guidance.

3. Below are instructions to run a UNIX shell script, a type of program. As I wrote above, it changes nothing. It doesn't send or receive any data on the network. All it does is to generate a human-readable report on the state of the computer. That report goes nowhere unless you choose to share it. If you prefer, you can act on it yourself without disclosing the contents to me or anyone else.

You should be wondering whether you can believe me, and whether it's safe to run a program at the behest of a stranger. In general, no, it's not safe and I don't encourage it.

In this case, however, there are ways for you to decide whether the program is safe without having to trust me. First, you can read it. Unlike an application that you download and click to run, it's transparent, so anyone with the requisite skill can verify what it does.

You may not be able to understand the script yourself. But variations of it have been posted on this website thousands of times over a period of years. The site is hosted by Apple, which does not allow it to be used to distribute harmful software. Any one of the millions of registered users could have read the script and raised the alarm if it was harmful. Then I would not be here now and you would not be reading this message. See, for example, this discussion.

Another indication that the test is safe can be found in this thread, and this one, for example, where the comment in which I suggested it was recommended by one of the Apple Community Specialists, as explained here.

Nevertheless, if you can't satisfy yourself that these instructions are safe, don't follow them. Ask for other options.

4. Here's a general summary of what you need to do, if you choose to proceed:

☞ Copy a particular line of text to the Clipboard.

☞ Paste into the window of another application.

☞ Wait for the test to run. It usually takes a few minutes.

☞ Paste the results, which will have been copied automatically, back into a reply on this page.

These are not specific instructions; just an overview. The details are in parts 7 and 8 of this comment. The sequence is: copy, paste, wait, paste again. You don't need to copy a second time.

5. Try to test under conditions that reproduce the problem, as far as possible. For example, if the computer is intermittently slow, run the test during a slowdown.

You may have started up in safe mode. If the system is now in safe mode and works well enough in normal mode to run the test, restart as usual before running it. If you can only test in safe mode, do that.

6. If you have more than one user, and only one user is affected by the problem,, and the affected user is not an administrator, then please run the test twice: once while logged in as the affected user, and once as an administrator. The results may be different. The user that is created automatically on a new computer when you start it for the first time is an administrator. If you can't log in as an administrator, test as the affected user. Most personal Macs have only one user, and in that case this section doesn’t apply. Don't log in as root.

7. Load this linked web page (on the website "Pastebin.") Press the key combination command-A to select all the text, then copy it to the Clipboard by pressing command-C.

8. Launch the built-in Terminal application in any one of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad and start typing the name.

Click anywhere in the Terminal window to activate it. Paste from the Clipboard into the window by pressing command-V, then press return. The text you pasted should vanish immediately.

9. If you see an error message in the Terminal window such as "Syntax error" or "Event not found," enter

exec bash

and press return. Then paste the script again.

10. If you're logged in as an administrator, you'll be prompted for your login password. Nothing will be displayed when you type it. You will not see the usual dots in place of typed characters. Make sure caps lock is off. Type carefully and then press return. You may get a one-time warning to be careful. If you make three failed attempts to enter the password, the test will run anyway, but it will produce less information. If you don't know the password, or if you prefer not to enter it, just press return three times at the password prompt. Again, the script will still run.

If the test is taking much longer than usual to run because the computer is very slow, you might be prompted for your password a second time. The authorization that you grant by entering it expires automatically after five minutes.

If you're not logged in as an administrator, you won't be prompted for a password. The test will still run. It just won't do anything that requires administrator privileges.

11. The test may take a few minutes to run, depending on how many files you have and the speed of the computer. A computer that's abnormally slow may take longer to run the test. While it's running, a series of lines will appear in the Terminal window like this:

Test started

Part 1 of 4 done at: … sec

Part 4 of 4 done at: … sec

The test results are on the Clipboard.

Please close this window.

The intervals between parts won't be exactly equal, but they give a rough indication of progress.

Wait for the final message "Please close this window" to appear. If you don't see it within about 15 minutes, the test probably won't complete in a reasonable time. In that case, press the key combination control-C or command-period to stop it. Then go to the next step. You'll have incomplete results, but still something. If you close the Terminal window while the test is still running, the partial results won't be saved and you'll have to start over.

12. When the test is complete, or if you stopped it because it was taking too long, quit Terminal. The results will have been saved to the Clipboard automatically. They are not shown in the Terminal window. Please don't copy anything from there. All you have to do is start a reply to this comment and then paste by pressing command-V again.

At the top of the results, there will be a line that begins with the words "Start time." If you don't see that, but instead see a mass of gibberish, you didn't wait for the "close this window" message. Please wait for it and try again.

If any private information, such as your name or email address, appears in the results, anonymize it before posting. Usually that won't be necessary.

13. When you post the results, you might see an error message on the web page: "You have included content in your post that is not permitted," or "The message contains invalid characters." That's a bug in the software that runs this website. Please post the test results on Pastebin, then post a link here to the page you created.

If you have an account on Pastebin, please don't select Private from the Paste Exposure menu on the page, because then no one but you will be able to see it.

14. This is a public forum, and others may give you advice based on the results of the test. They speak for themselves, not for me. The test itself is harmless, but whatever else you're told to do may not be. For others who choose to run it, I don't recommend that you post the test results on this website unless I asked you to.

______________________________________________________________

Copyright © 2014, 2015 by Linc Davis. As the sole author of this work (including the referenced "Diagnostic Test"), I reserve all rights to it except as provided in the Use Agreement for the Apple Support Communities website ("ASC"). Readers of ASC may copy it for their own personal use. Neither the whole nor any part may be redistributed.

Dec 24, 2015 10:06 AM in response to shane785300

A

Some of your user files (not system files) have incorrect permissions or are locked. This procedure will unlock those files and reset their ownership, permissions, and access controls to the default. If you've intentionally set special values for those attributes, they will be reverted. In that case, either stop here, or be prepared to recreate the settings if necessary. Do so only after verifying that those settings didn't cause the problem. If none of this is meaningful to you, you don't need to worry about it, but you do need to follow the instructions below.

Please back up all data before proceeding.

Step 1

If you have more than one user, and the one in question is not an administrator, then go to Step 2.

Enter the following command in the Terminal window in the same way as before (triple-click, copy, and paste):

sudo find ~ $TMPDIR.. -exec chflags -h nosappnd,noschg,nosunlnk,nouappnd,nouchg {} + -exec chown -h $UID {} + -exec chmod +rw {} + -exec chmod -h -N {} + -type d -exec chmod -h +x {} + 2>&-

You'll be prompted for your login password, which won't be displayed when you type it. Type carefully and then press return. You may get a one-time warning to be careful. If you don’t have a login password, you’ll need to set one before you can run the command. If you see a message that your username "is not in the sudoers file," then you're not logged in as an administrator.

The command may take several minutes to run, depending on how many files you have. Wait for a new line ending in a dollar sign ($) to appear, then quit Terminal.

Step 2 (optional)

Take this step only if you have trouble with Step 1, if you prefer not to take it, or if it doesn't solve the problem.

Start up in Recovery mode. You may be prompted to select a language, then the OS X Utilities screen will appear.

If you use FileVault 2, select Disk Utility, then select the icon of the FileVault startup volume ("Macintosh HD," unless you gave it a different name.) It will be nested below another drive icon. Click the Unlock button in the toolbar and enter your login password when prompted. Then quit Disk Utility to be returned to the main screen.

Select

Utilities Terminal

from the menu bar. A Terminal window will open. In that window, type this:

resetp

Press the tab key. The partial command you typed will automatically be completed to this:

resetpassword

Press return. A Reset Password window will open. You’re not going to reset a password.

Select your startup volume ("Macintosh HD," unless you gave it a different name) if not already selected.

Select your username from the menu labeled Select the user account if not already selected.

Under Reset Home Directory Permissions and ACLs, click the Reset button.

Select

Restart

from the menu bar.

B

Back up all data.

Run the following command in the same way as before. It moves to the Trash "semaphore" files that have not been cleaned up by the system and may be interfering with normal operation. The files are empty; they contain no data. There will be no output this time.

find L*/{Con*/*/Data/L*/,}Pref* -type f -size 0c -name *.plist.??????? -exec mv {} .Trash/ \; 2>&-

Log out or restart the computer and empty the Trash.

C

"CleanMyMac" is a scam and a common cause of instability and poor performance. Depending on what version you have, the developer's instructions may not completely remove it. Please follow those instructions, then do as below.

Please back up all data before proceeding.

Triple-click anywhere in the line below on this page to select it:

/Library/LaunchDaemons/com.macpaw.CleanMyMac2.Agent.plist

Right-click or control-click the highlighted line and select

Services Reveal in Finder (or just Reveal)

from the contextual menu.* A folder may open with an item selected. If it does, move the selected item to the Trash. You may be prompted for your administrator login password.

Repeat with this line:

/Library/PrivilegedHelperTools/com.macpaw.CleanMyMac2.Agent

Restart the computer and empty the Trash.

You may also have to remove one or more of these items in the same way:

~/Library/LaunchAgents/com.macpaw.CleanMyMac.helperTool.plist

~/Library/LaunchAgents/com.macpaw.CleanMyMac.volumeWatcher.plist

~/Library/LaunchAgents/com.macpaw.CleanMyMac3.Scheduler.plist

Never again install "CleanMyMac" or anything like it.

*If you don't see the contextual menu item, copy the selected text to the Clipboard by pressing the key combination command-C. In the Finder, select

Go Go to Folder...

from the menu bar and paste into the box that opens by pressing command-V. You may not see what you pasted because a line break is included. Press return.

D

Please remove "AppBarrier," "ContentBarrier," "NetBarrier," and/or "VirusBarrier" by following the instructions on this page. If you have a different version, the procedure may be different.

Back up all data before making any changes. Never install any "anti-virus" or "anti-malware" product again.

E

Please uninstall "SIMBL" or "EasySIMBL" as follows. Back up all data before making any changes.

Triple-click anywhere in the line below on this page to select it, then copy the text to the Clipboard by pressing the key combination command-C:

/Library

In the Finder, select

Go Go to Folder...

from the menu bar, paste into the box that opens by pressing command-V, then press return. A folder will open. From that folder, delete the items listed below (some may be absent.) You may be prompted for your administrator login password.

Application Support/SIMBL

InputManagers/SIMBL

LaunchAgents/net.culater.SIMBL.Agent.plist

LaunchAgents/net.infinite-labs.SIMBLEnablerForSandboxedApps.plist

ScriptingAdditions/EasySIMBL.osax

ScriptingAdditions/SIMBL.osax

Log out and log back in. There may also be an item named "EasySIMBL" in the Applications folder. Delete it, if so.

Make sure you never reinstall any variant of SIMBL. It’s likely to come bundled with another third-party system modfication that depends on it. If you want trouble-free computing, avoid software that makes miraculous changes to other software, especially built-in applications. Possible exceptions to that rule include app extensions from the App Store and Safari extensions, which are mostly safe, and are easy to get rid of when they don’t work. SIMBL and its dependents are not in either of those categories.

F

Please back up all data before proceeding.

Launch the Font Book application and validate all fonts. You must select the fonts in order to validate them. See the built-in help and this support article for instructions. If Font Book finds any issues, resolve them.

Start up in safe mode to rebuild the font caches. Restart as usual and test.

Note: If FileVault is enabled in OS X 10.9 or earlier, or if a firmware password is set, or if the startup volume is a software RAID, you can’t start in safe mode. In that case, ask for instructions.

If you still have problems, then from the Font Book menu bar, select

FileRestore Standard Fonts...

You'll be prompted to confirm, and then to enter your administrator login password.

Also note that if you deactivate or remove any built-in fonts, for instance by using a third-party font manager, the system may become unstable.

G

The system is running very slowly.

None of the following system modifications serves any real purpose. All should be removed unconditionally:

TechTool Pro

These system modifications may do something useful to you, but any or all could be contributing to the problem:

Snagit or Camtasia

WireTap Studio or Snapz Pro

If you want to keep them, do a trial removal to find out whether they're at fault, and refer to the developers for support if they are. Some or all may need to be updated.

Any third-party software that doesn't install from the App Store or by drag-and-drop into the Applications folder, and uninstall by drag-and-drop to the Trash, is a system modification.

Whenever you remove system modifications, they must be removed completely, and the only way to do that is to use the uninstallation tool, if any, provided by the developers, or to follow their instructions. If the software has been incompletely removed, you may have to re-download or even reinstall it in order to finish the job.

I never install system modifications myself, and except as stated in this comment, I don't know how to uninstall them. You'll have to do your own research to find that information.

Here are some general guidelines to get you started. Suppose you want to remove something called “BrickMyMac” (a hypothetical example.) First, consult the product's Help menu, if there is one, for instructions. Finding none there, look on the developer's website, say www.brickmymac.com. (That may not be the actual name of the site; if necessary, search the Web for the product name.) If you don’t find anything on the website or in your search, contact the developer. While you're waiting for a response, download BrickMyMac.dmg and open it. There may be an application in there such as “Uninstall BrickMyMac.” If not, open “BrickMyMac.pkg” and look for an Uninstall button. The uninstaller might also be accessed by clicking the Customize button, if there is one.

Back up all data before making any changes.

You will generally have to restart the computer in order to complete an uninstallation. Until you do that, there may be no effect, or unpredictable effects.

If you can’t remove software in any other way, you’ll have to erase and install OS X. Never install any third-party software unless you're sure you know how to uninstall it; otherwise you may create problems that are very hard to solve.

Trying to remove complex system modifications by hunting for files by name often will not work and may make the problem worse. The same goes for "utilities" such as "AppCleaner" and the like that purport to remove software.

H

A recent update to "Flash Player" installs a background process that is designed to send information back to Adobe without the user's knowledge or consent. Adobe did not announce that change in behavior, and in fact it claims that the change was a mistake.

I don't know what, if any, data is being sent to Adobe. If you don't care, there's no need to do anything. If you're concerned, you can disable the process permanently as follows. It should remain disabled even when Flash is updated again—although Adobe could, if it so chose, override your decision in its installer. The only way to be sure that won't happen is to remove Flash and never install it again.

Back up all data before proceeding.

Please enter the following command in a Terminal window as before:

sudo launchctl disable system/com.adobe.SC.FPFeedbackService-1.0

There should be no output. If you change your mind and want the process to run again, enter this command:

sudo launchctl enable system/com.adobe.SC.FPFeedbackService-1.0


I

You're on a Wi-Fi network that uses the obsolete and insecure WEP security standard. If it's your network, that's very dangerous. Please change your router's settings so that it uses WPA 2 Personal security. If it doesn't support that standard, it should be replaced. I can't give you specific instructions for changing the setting, because all routers are different. Refer to the manufacturer's documentation.

J

In the sidebar of a Finder window, or on the Desktop, please select the icon of the startup volume ("Macintosh HD," unless you gave it a different name.) Open it. Inside, there is a folder named "lost+found". It contains one or more corrupt files that are wasting a lot of storage space. Back up all data, then drag the folder to the Trash and empty. You may be prompted for your administrator password.

Dec 24, 2015 3:21 PM in response to Linc Davis

Hi Again!😎


Great info and directions!!! I really appreciate the support and recommendations, no wonder you are a rock star in the Mac world. I also appreciate the educational nuggets.


The short version: The mystery window solved.


Followed your directions to the "t", in order.


Culprit: Phoneclean.


The box was remnant of the "silentcleanserver" process I caught in the activity monitor. Since it was only happening to my account, I started with just my user activity and tried to catch the process by when the window showed up and what was active in the monitor. After a few incorrect guesses, I found the real issue. I had to reload the software and then delete it to get it to stop running the process, just doing it in the activity monitory didn't work. Then I found this Silent Clean Server!


Again, I really, really appreciate your patience and exemplary support.


Some following on, tangential questions if I may:

1. If I understand your advocacy properly, you do not recommend a third-party firewall or virus protection for a mac?

2. Is there a defrag/utility program you would suggest?


Thanks for helping me out so kindly and thoroughly! Have a great Holiday!


ps. mac is running quicker too 🙂

Jan 5, 2016 3:40 PM in response to shane785300

How to maintain a Mac

Make two or more backups of all your files

One backup is not enough to be safe. A copy of a backup doesn't count as another backup; all backups must be made directly from the original data.

Keep at least one backup off site at all times in case of disaster. Backing up to a cloud-data service is one way to meet this need, but don't rely exclusively on such backups.

In fact, don’t rely on any single backup method, such as Time Machine.

If you get an indication that a backup has failed, don't ignore it.

Keep your software up to date

In the App Store or Software Update preference pane (depending on the OS version), you can configure automatic notifications of updates to OS X and other Mac App Store products. Some third-party applications from other sources have a similar feature, if you don’t mind letting them phone home. Otherwise you have to check yourself on a regular basis.

Keeping up to date is especially important for complex software that modifies the operating system, such as device drivers. Don't install such modifications unless they're absolutely necessary. Remove them when they are no longer needed. Before installing any Apple update, you must check that all system modifications that you use are compatible. Incompatibility with third-party software is by far the most common cause of difficulties with system updates.

Don't install crapware

...such as “themes,” "haxies," “add-ons,” “toolbars,” “enhancers," “optimizers,” “accelerators,” "boosters," “extenders,” “cleaners,” "doctors," "tune-ups," “defragmenters,” “firewalls,” "barriers," “guardians,” “defenders,” “protectors,” most “plugins,” "virus scanners,” "disk tools," or "utilities." With very few exceptions, such stuff is useless or worse than useless. Above all, avoid any software that purports to change the look and feel of the user interface.

It's not much of an exaggeration to say that the whole "utility" software industry for the Mac is a fraud on consumers. The most extreme examples are the "CleanMyMac," "TuneUpMyMac," and “MacKeeper” scams, but there are many others.

As a rule, you should avoid software that changes the way other software works. Plugins for Photoshop and similar programs are an obvious exception to this rule. The Mac App Store has extensions for the Photos app, and perhaps others, that should be safe. Safari extensions, and perhaps the equivalent for other web browsers, are a partial exception. Most are safe, and they're easy to get rid of if they don't work. Some may cause the browser to crash or otherwise malfunction. Some are malicious. Use with caution, and install only well-known extensions from relatively trustworthy sources, such as the Safari Extensions Gallery.

Only install software that directly enables you to do something that you need the computer for. For example, a word processor enables you to write. A video editor enables you to make movies. A game enables you to have fun. But a "cache cleaner" or a "malware scanner" doesn't enable you to do anything. You didn't buy a computer so you could clean its caches or scan it for malware. Just say no to anyone who wants you to do such things.

Never install any third-party software unless you know how to uninstall it. Otherwise you may create problems that are very hard to solve. Do not rely on "utilities" such as "AppCleaner" and the like that purport to remove software.

Don't install bad, conflicting, or unnecessary fonts

Whenever you install new fonts, use the validation feature of the built-in Font Book application to make sure the fonts aren't defective and don't conflict with each other or with others that you already have. See the built-in help and this support article for instructions.

Deactivate or remove fonts that you don't really need to speed up application launching.

Avoid malware

"Malware" is malicious software that circulates on the Internet. That kind of attack on OS X was once so rare that it was hardly a concern, but it's now increasingly common and dangerous.

There is some built-in protection against malware, but you can’t rely on it—the attackers are always at least a day ahead of the defense. You can’t rely on third-party "anti-virus" or "anti-malware" products for protection either. The only safety lies in safe computing practices. The "anti-virus" industry will always try to persuade you that you're helpless to protect yourself from malware attack unless you use its products. You're not helpless—rather, that industry is helpless to protect you, just as it's helpless to protect Windows and Android users, whose platforms are infested with malware despite $75 billion in annual sales of "anti-virus" software.

Never install software from an untrustworthy or unknown source. If in doubt, do some research. Any website that prompts you to install a “codec” or “plugin” that comes from the same site, or an unknown site, is untrustworthy. Software that doesn't come from the Mac App Store, such as Adobe Flash Player, must come directly from the developer's website. No intermediary is acceptable, and don’t trust links unless you know how to parse them. Any file that is automatically downloaded from the web, without your having requested it, should go straight into the Trash. A web page that tells you that your computer has a “virus,” or that anything else is wrong with it, is a scam.

In OS X 10.7.5 or later, downloaded applications and Installer packages that have not been digitally signed by a developer registered with Apple are blocked from loading by default. The block can be overridden, but think carefully before you do so.

Because of recurring security issues in Java, it’s best to disable it in your web browsers, if it’s installed. Few websites have Java content nowadays, so you won’t be missing much. This action is mandatory if you’re running any version of OS X older than 10.6.8 with the latest Java update. Note: Java has nothing to do with JavaScript, despite the similar names. Don't install Java unless you're sure you need it. Most people don't.

Don't fill up your disk or SSD

A common mistake is adding more and more large files to your home folder until you start to get warnings that you're out of space, which may be followed in short order by a startup failure. This is more prone to happen on the newer Macs that come with an internal SSD instead of the traditional hard drive. The drive can be very nearly full before you become aware of the problem.

While it's not true that you should or must keep any particular percentage of space free, you should monitor your storage use and make sure you're not in immediate danger of using it up. According to Apple documentation, you need at least 9 GB of free space on the startup volume for normal operation.

If storage space is running low, use a tool such as OmniDiskSweeperto explore the volume and find out what's taking up the most space. Move seldom-used large files to secondary storage.

Relax, don’t do it

Besides the above, no routine maintenance is necessary or beneficial for the vast majority of users; specifically not “cleaning caches,” “zapping the PRAM,” "resetting the SMC," “rebuilding the directory,” "defragmenting the drive," “running periodic scripts,” “dumping logs,” "deleting temp files," “scanning for viruses,” "purging memory," "checking for bad blocks," "testing the hardware," or “repairing permissions.” Such measures are either completely pointless or are useful only for solving problems, not for prevention.

To use a Mac effectively, you have to free yourself from the Windows mindset that every computer needs regular downtime for maintenance such as "defragging" and "registry cleaning." Those concepts do not apply to the Mac platform.

A well-designed computing device is not something you should have to think about much. It should be an almost transparent medium through which you communicate, work, and play. If you want a machine that needs a lot of attention just to keep going, use a PC, or collect antique cars.

The very height of futility is running an expensive third-party application called “Disk Warrior” when nothing is wrong, or even when something is wrong and you have backups, which you must have. Disk Warrior is a data-salvage tool, not a maintenance tool, and you will never need it if your backups are adequate. Don’t waste money on it or anything like it.

How to get rid of mysterious window outline?

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