This could be the result of a known bug, it is not actually closing firefox, but clearing cookies or history that causes the problem. It even occurs if plugins are disabled!!

(You probably have no choice but to put up with this until developers get round to fixing the bug - Bug 633427 - Clearing cookies launches instance of plugin-container for each plugin installed )

Try ensuring firefox does not clear cookies or History when it closes, is that a workaround that stops the problem?

The bug mentioned probably does not normally cause firefox to crash, in your case there could be an additional problem, possibly malware.

Yeah, not clearing cookies or history was even worse. I didn't get as many plugin-containers, but it did launch Acrobat, and ever after I killed Acrobat, it took forever for Firefox to quit. About 15 minutes. I guess I'll just have to wait for the fix. Thank goodness for the task manger.

Your system details Aside indicate you are using Acrobat 6, that is out of date I suggest you update it, I daresay older versions may have problems including security vulnerabilities. With all your plugins enabled visit:

• http://www.mozilla.org/en-US/plugincheck/

If your problems happen when NOT clearing cookies (or History including cookies) your problem is apparently something other than the bug I mentioned. Remember though that Firefox may be set to automatically clear History. Also note the bug silently opens plugincontainer.exe instances, not windows of plugins.

Are you actually seeing open windows e.g. of the Acrobat instance ? if so I am leaning towards suspicion the problem could be malware

• see is my firefox problem a result of malware
  use multiple tools/sites to run malware checks

No, windows are not opening. I see all the plugin-containers in the Task Manager. Acrobat does not open in a separate window. I get the splash screen just like when I click on a link to a PDF, but no separate window opens. I know I'm using an old version of Acrobat; it was part of a bundle I haven't seen fit to update. I know I should; I just haven't. I'll try the plugin check tonight and post results.

I have had the same problem for weeks and posted it actually. It just eats up memory while opening a lot of plugin containers and Acrobat, which always causes a problem anyway, Adobe side, for my old laptop. I even have disabled Acrobat distiller, etc., but no luck. I have luck if I delete cookies individually, and then delete the rest of the history. But, that is a cross your fingers, holding your breath type of thing, because it still happens sometimes then. I am surprised that there hasn't been a fix for this because it's been a few weeks since I posted, and there were several posting with me. Hope someone can help!! Thanks!!

Note anyone suffering from the effects of above mentioned bug633427, that this is a very unusual bug in that it is one where disabling the plugins in Firefox does NOT help.

Jedchase
I suggest you post your own questions with full details. (use this link )The last thread you posted in /questions/792258 seems related to

• a specific error message
• involved quicktime use in some problems / solutions
• has many posts and thousands of votes,
  • but may well have meandered over a few other problems,
  • and is old initially having been started in relation to Firefox 3.6