Q: Preview app problem

What kind of files? How do you try to open them? What happens when you try to open a file with preview?

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

          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.

The usual first troubleshooting step is to quit Preview then go to your Home Library folder (e.g., via pressing option while perusing the Finder Go menu) then trashing all files "com.apple.preview...." .

If that fixes it, great.  If not, a next troubleshooting step is to see if the bad behavior persists when (1) logging in as a different user, (2) starting up in Safe Mode.

-charlie

Good!

Hello. Could you tell what exactly helped you?

Read the post by CT marked solved.

Eric Root, I red it well.

But what does it mean " -charlie"?

My monitor is too bright, any application I open will go too bright. Can't adjust anything. I am using OS X 10.9.5...I can't even see the space where I have to type something. Tried everything but does not work.

Thank you,

That is CT's name.

You might want to consider starting a new discussion. Since this one is marked solved, less people are likely to look at it. You can link to this one.