Okay, so we get squeamish when it comes to messing with our Macs. I’m right there with you. If something goes wrong my first instinct is to ask for help. In my case I have a certified Apple technician in the family who really likes my home made chicken pie and banana pudding. It is fairly easy to yell “help”.
But this is something any one can do if you follow the steps carefully; and if you don’t happen to have a certified Apple technician in your family who really likes your chicken pie and/or banana pudding, it may save you a trip to the repair shop.
The presenting problem is one specific application starts acting weird when everything else is working OK. And this isn’t limited to third party applications. It can be Safari, or iChat or any of your regular Apple applications as well.
Deleting the plist(s)
Before you try this make sure you have a copy of the registration code for your application. Sometimes, not often, you will have to re-enter the registration code after deleting the plist(s).
This problem can frequently be solved by deleting the plist(s) that are specific to that application. The plists are part of the preferences and sometimes they just get corrupted.
Make sure your application is not open.
Open a Finder Window > your Home folder > Library.
Scroll down until you see the start of a long list of plist items and find the one(s) that match the application that is giving you trouble.
Drag it/them to your Desktop. If the file(s) turn out to be the culprit you can erase it/them by dragging them to the trash and emptying the trash.
DO NOT remove the com.apple.mail.plist without backing up your Mail folder in the user library. You could end up losing all of your mail.
Open your application. New plist(s) will automatically be created and your problem may well be solved. If it is not, you can drag the original plist file(s) back to their original location.
I have used this technique a half dozen times and it has solved the problem every time.
Following are two examples of what you need to look for when searching for plist files.
In this example there are 4 plists for iChat. All 4 would have to be deleted.
In this example the name of the developer comes before the name of the actual application.