Mac OS X: Finding & Fixing Corrupt Preference Files

One of the more common causes for unusual behavior on the Mac is a corrupt preference file, especially if the symptom is a program that won’t open or one that crashes frequently. Preference files store all sorts of application-specific information, everything from what your browser’s home page is to your default Mail font settings, and even some things you might not think about, like what shortcuts you keep in your Finder sidebar. Here are some handy-dandy ideas, though, on how to correct the problem if you suspect one’s gone rogue.

If you quit the offending program, you can then look in [Your Home Folder]/Library/Preferences for the associated file. They’re almost always named in this manner:

com.[name of the software vendor].[name of the application].plist

So, for example, the Finder’s preference file is named, and the one for PDFpen is com.smileonmymac.PDFpen.plist.


Here’s a list of the extremely exciting preference files I have on my machine. I command you to be interested.


Once you’ve found the allegedly corrupt preference file, delete it. The next time you launch the persnickety application, it’ll rebuild a default version of that file, and if your problem’s gone, you can pat yourself on the back. Or tell other people what you’ve done so they can pat you instead, which may be more satisfying. 

If the problem isn’t resolved by that, you can always put the old preference file back where you got it (with the application in question not running), and all of the customization options you chose for that program will return. Another important thing to know is that some preference files live within the /Library/Preferences folder at the top level of your hard drive, but you’ll need to be a bit more cautious mucking around in there (and you’ll have to authenticate as an administrator to make any changes if you’re not already logged in as one). Preference files stored in that location can affect all users of your machine, so the implications are a bit far-reaching. The same scenario applies, though—if you find that deleting the file didn’t fix the problem, you can always put it back.

If only everything in life were so easy. I’d delete so many people’s corrupt music preference files that Justin Bieber might just cease to exist.