Q: Problem description: My computer is running very slow ever since I switched to Yosemite.  I get the multicolored wheel just opening my browser at times and waiting for a page to open, or an application.  Any ideas other than rebooting my computer to

I see no Norton Anti-virus and Symantec anywhere on my computer.

That's because Norton Antivirus is not on your computer. You installed it about five years ago and removed it later.

The danger of running that test script, and then not posting the results promptly, is that the information it produces will be read by others. Then you'll get advice of the same quality as you would get from posting "etrecheck" output, or worse. The test results are not intended for anyone else's use. I unsubscribed from this thread one day after you failed to respond to my request for information, and I saw only by chance that you had finally replied.

A

You're using the "legacy" (pre-Lion) version of FileVault (LFV) as well as FileVault 2. LFV is obsolete and should not be used under OS X 10.7 or later.

When LFV is active, your home folder is only backed up by Time Machine when you log out. If you use Time Machine and haven't logged out recently, do that now so the backups can be updated. If you use third-party backup software, the backups may or may not be up to date, depending on how the software works.

After backing up, follow the instructions on this support page under the heading "Migrating a Legacy FileVault home folder from an earlier version of OS X." You might get an alert that there isn't enough disk space to deactivate LFV. If so, see this support page.

B

The worthless "MacScan" is at least partially installed. You should remove it.

Any third-party software that doesn't install 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.

C

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.

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 nouchg,nouappnd,noschg,nosappnd {} + -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. When the OS X Utilities screen appears, 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.

D

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.

E

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

          File ▹ Restore 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.

F

Storing many files on the Desktop may slow down the Finder, especially if the files have custom icons. Move most or all of the files to another subfolder of your home folder.

G

The symbol cache file is very large. It stores data used in logs and crash reports, and it may have grown because there have been a lot of crashes. The file is created automatically, and if deleted, it should be recreated when you restart the computer. Initially, at least, it will be a lot smaller.

I've seen one unverified report that a system became unbootable when the cache was deleted. That would have been due to a corrupt installation of OS X, but you should be prepared to reinstall if necessary. There is no reason to panic as long as you have good backups, which you should already have if you got this far.

Enter the following command in the same way as before:

sudo mv /S*/*/Caches/com.apple.coresymbolicationd /tmp/

Restart the computer.