Bugs & Fixes: Solving a mysterious plug-in crash

With Mac OS X 10.5 (Leopard), Apple added a helpful new troubleshooting feature to the "unexpectedly quit" dialog. Because the addition only pops up occasionally, I had never had any personal experience with it until last week. However, its appearance on my Mac turned out to be the key to a quick resolution of the problem.

The new text appears if Mac OS X detects that the cause of an application crash may actually be a plug-in file that is working with or along side of the application. In such cases, the familiar "application quit unexpectedly" text is followed by a less familiar sentence: "The problem may have been caused by the plug-in."

In my case, this text appeared after a crash of the . However, its appearance is certainly not limited to Safari. A search of the Web reveals that this plug-in message can occur after crashes of iTunes, Pages, Motion, Final Cut Pro, and numerous other applications.

Here are the specifics for my crash: Via a (Flash) Web app running at , I attempted to open and load a photo file from my Mac. While the Open dialog was on the screen, Safari crashed. The message that next appeared informed me that "The problem may have been caused by the Cocoa Patcher plug in." This was not just a one time glitch; it happened repeatedly.

(Image Caption: Unexpected quit messages in Leopard can sometimes pinpoint the problem to a plugin)

My next step was to search for the suspect plug-in. Unfortunately, a Spotlight search came up empty. Even searching in various Library folders yielded no results.