How to Delete a Preferences File
The preferences file is what a program uses to remember your preferences. Perhaps you don’t want to use automatic bullets or numbering, for instance, or you want to use a specific font by default. If you have a Preferences file for an application that has been uninstalled, you don’t need its Preferences file anymore. If the application has begun to act weird, you can often delete this file to resolve the problem. Preferences files are located in your personal Library folder, in a folder called Preferences.
Preferences files end in .plist. To delete these files, follow these steps:
1. Open the Finder and select your user name.
2. Open the Library folder and then the Preferences folder.
3. Work through the list, deleting files associated with programs you have previously deleted or for an application that is acting odd.
4. To delete the file, Control+click it and choose Delete.
Caution! Don’t delete preferences files if you don’t know what program they’re associated with!
There are two more Preferences folders. Besides the one in your Home folder, there’s another in the hard drive window whose files can only be deleted by an administrator. There’s probably not enough in there to warrant risking deleting them, but you can open and browse around in there if you want. Just don’t delete anything if you don’t know what it does! The third Preferences folder is inside the System>Library folder and can’t be trashed by anyone.
Tip: If you have a System 9 System Folder on your Macintosh HD, open it and look at the Preferences folder there too. Remember to only delete preferences files for programs you recognize and have previously deleted.
Preferences Files Can Cause Problems
A corrupt preferences file can cause a program to behave erratically. It can, for example, cause crashes when the program opens or when a document needs to be saved. Deleting a preferences file can thus be used to troubleshoot an application.
If an application is behaving erratically, log in using a different user account, open the program, and see if you can replicate the problematic behavior. If you can’t, the problem may lie with your personal preferences file. To test that theory, log back on using your user account, delete the preferences file for that program, and then restart the program. On restart, the program will create a brand new preferences file, which should solve the problem. (You’ll have to re-create your preferences if this solves the problem.) If the problem still exists, salvage the old preferences file from the Trash and continue troubleshooting.