Quicklook doesn't show PDF files

Back up all data before proceeding.

This procedure will unlock all your user files (not system files) and reset their ownership, permissions, and access controls to the default. If you've intentionally set special values for those attributes on any of your files, 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.

Step 1

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

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

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>&-

Copy the selected text to the Clipboard by pressing the key combination command-C.

Launch the built-in Terminal application in any 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.

Paste into the Terminal window by pressing command-V. I've tested these instructions only with the Safari web browser. If you use another browser, you may have to press the return key after pasting.

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.

Back up all data. Quit Preview if it's running.

Hold down the option key and select Go ▹ Library from the Finder menu bar. From the Library folder, delete the following items, if they exist:

Containers/com.apple.Preview

Containers/com.apple.quicklook.ui.helper

Group Containers/com.apple.Preview

Preferences/com.apple.Preview.LSSharedFileList.plist

Preferences/com.apple.Preview.SandboxedPersistentURLs.LSSharedFileList.plist

Saved Application State/com.apple.Preview.savedState

Log out and log back in. Launch the application and test.

Hi @pps4Me,

When did this start happening?

I wrote a little diagnostic program to help show what might be causing these problems. Download EtreCheck from http://www.etresoft.com/etrecheck, run it, and paste the results here. EtreCheck is perfectly safe to run, does not ask for your password to install, and is signed with my Apple Developer ID.

Disclaimer: Although EtreCheck is free, there are other links on my site that could give me some form of compensation, financial or otherwise.

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.

Back up all data before proceeding.

This procedure will unlock all your user files (not system files) and reset their ownership, permissions, and access controls to the default. If you've intentionally set special values for those attributes on any of your files, 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.

Step 1

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

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

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>&-

Copy the selected text to the Clipboard by pressing the key combination command-C.

Launch the built-in Terminal application in any 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.

Paste into the Terminal window by pressing command-V. I've tested these instructions only with the Safari web browser. If you use another browser, you may have to press the return key after pasting.

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.

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, 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 a couple of 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 necessary 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.

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 sometimes, but not always, 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. If you can only test in safe mode, do that.

6. If you have more than one user, and the one affected by the problem 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.") The title of the page is "Diagnostic Test." Below the title is a text box headed by three small icons. The one on the right represents a clipboard. Click that icon to select the text, then copy it to the Clipboard on your computer by pressing the key combination command-C.

If the text doesn't highlight when you click the icon, select it by triple-clicking anywhere inside the box. Don't select the whole page, just the text in the box.

8. Launch the built-in Terminal application in any 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 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:

[Process started]

Part 1 of 8 done at … sec
…
Part 8 of 8 done at … sec

The test results are on the Clipboard.

Please close this window.

[Process completed]

The intervals between parts won't be exactly equal, but they give a rough indication of progress. The total number of parts may be different from what's shown here.

Wait for the final message "Process completed" to appear. If you don't see it within about ten 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 and go to the next step. You'll have incomplete results, but still something.

12. When the test is complete, or if you stopped it because it was taking too long, quit Terminal. The results will have been copied 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 "Process completed" message to appear in the Terminal window. 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 forum software. Please post the test results on Pastebin, then post a link here to the page you created.

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.

Hello again @pps4Me,

You have a large number of system modifications on that machine. My official recommendation would be to wipe the machine and reinstall the operating system. Then, restore only your user documents from backup. Manually reinstall only the applications that you really need and only after you have verified that they work properly on Yosemite.

Can you explain how your hard drives are configured? Your boot device is an SSD but your home directory is on a different hard disk. How did you set that up? You said above that other users are not affected by this problem. Are the home directories of those other users on the boot disk or the other disk? Some of Linc's diagnostic steps may not have worked properly with this setup.

Hello again @pps4Me,

Although you have a Time Machine backup, it is always a good idea to make another backup somewhere. Time Machine is great for those times that you didn't realize that you would need a back. If you know you are going to be wiping your system and reinstalling, you should definitely have an additional backup. You can use one of the cloning tools like Carbon Copy Cloner or Super Duper!. You can also use Apple's Disk Utility (Disk Utility 12.x: Restore a disk image to a disk). Since your user files are on a separate disk, you will have to take extra care to make sure those are backed up.

You will probably have some difficulties restoring from backup due to your user directory on the other disk. I suggest that you create and use an "Administrator" account that is different than any of your previous accounts. Then, you can use Migration Assistant to migrate your old user account. If that fails or is incomplete, you may need to use the Administrator account to manually copy the files into /Users/Shared. Apple has instructions on how to change your home directory (Change your OS X account name and home directory name - Apple Support).

Hi

I feel wiping the machine might be poor advice, considering @pps4Me doesn't have the problem when logged in as a different user.

I have the same problem on two of my MacBook Pros. Both occurred after the latest system update for Yosemite.

I don't have enough knowledge on what exactly safe mode is, but I suspect it's booting the mac with all third-party influences turned off. If it is still occurring in Safe mode and not, when logged in as a different user, I would think there is a problem with 10.10.3. Going to the pains of reformatting and reinstalling (not to mention re-entering all new 3rd party license codes), without knowing what the problem is could mean the problem returning.

From my experience of the problem was firstly PDFs opening in a different app to preview (without me changing the default app for PDFs) and, at the same time, previewing from the print dialog not working any more. When I tried to open the PDFs from the Preview app, there was a third-party error for items downloaded from the internet. At this stage I have blank default pdf icons which Preview will not open and Preview is not longer the default app for PDFs.

If I try to change the default app in Finder's Get Info, it will not app ear as an option. If I pick Other, it is a greyed out app and if I force it by turning of Recommended, it still won;t open the file.

Hope this information helps get to the route & thanks for the help.