The application "preview" is not open anymore

Does Preview open at all? If not, go to Finder and select your user/home folder. With that Finder window as the front window, either select Finder/View/Show View options or go command - J. When the View options opens, check ’Show Library Folder’. That should make your user library folder visible in your user/home folder. Remove the following. You may not find them all.

Containers/com.apple.Preview

Preferences/com.apple.Preview.LSSharedFileList.plist

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

Saved Application State/com.apple.Preview.savedState

Credit Linc Davis for this solution.

I just had this happen for the first time on 10.11.

A quick fix in my case was simply opening Applications > Utilities > Activity Monitor, highlight the "Preview" process and hit Alt+Cmd+Q to end it. After that, Preview was back to normal operation.

Try Utilities>Disk Utility>First Aid> Repair Disk permissions

Restart the computer and try again.

My wife's computer had this yesterday too! I discovered that there was a preview running, but it was unresponsive. Oddly, force quit did not work on it, and the computer would not restart. I force rebooted the MacBook by holding down the power key and that worked (of course). Preview is happy once again.

Love it when I do exactly what you suggested, delete this and that, restart - & bingo! Thanks a lot

What worked for me was going into the Applications folder and duplicating the Preview application, then opening the duplicate.