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Firefox process occasionally continues to run after closing browser in XP Pro 64 and uses 50% CPU

  • 7 replies
  • 42 have this problem
  • 1 view
  • Paskiausią atsakymą parašė John99

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Every once in awhile after closing Firefox 3.6.13 the process continues to run. The way I discover this is my CPU temperature monitor is increasing from 36C to 50C, so I open the Task Manger and see that it is using 50% of the CPU, slowing down the computer. I am running XP Professional 64 bit SP2 with all the latest updates on an Intel E8400 3.0GHz overclocked to 3.6GHz and 4GB dual channel DDR2-1066 at 800MHz. This happens only occasionally, maybe once or twice a month. I just end the task and the temperature of the CPU drops and everything is normal again.

Every once in awhile after closing Firefox 3.6.13 the process continues to run. The way I discover this is my CPU temperature monitor is increasing from 36C to 50C, so I open the Task Manger and see that it is using 50% of the CPU, slowing down the computer. I am running XP Professional 64 bit SP2 with all the latest updates on an Intel E8400 3.0GHz overclocked to 3.6GHz and 4GB dual channel DDR2-1066 at 800MHz. This happens only occasionally, maybe once or twice a month. I just end the task and the temperature of the CPU drops and everything is normal again.

All Replies (7)

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No answer, but a question

Does this happen on a particular web page ? eg is it on a media stream of some sort, or is a download in progress ?

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It does not seem to happen on any particular webpage, although I am mostly browsing msnbc.msn.com, foxnews.com or news.yahoo.com. It seems to be random. I close Firefox, I can come back later and open Firefox without any trouble, but the previous instance is still running in the background consuming CPU time As I mentioned, the only way I know there is a problem is that the computer has slowed down and the CPU temperature has gone up to 50C.

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It may be malware, it could be worth running a security scan on your computer.

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Nope. System clean. Scanned every morning at 1AM while I'm sleeping.

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I have this problem with 4.0 as well. It's any time (i.e., not particular web page) you try to close the browser. I do not have malware on my pc.

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Not sure this will help but I have a similar problem with the FireFox process continuing to run despite the application being closed. I narrowed this down to the Symantec IPS add-on/extension. Unfortunately I haven't found a solution as of yet other than disabling the extension. http://community.norton.com/t5/Norton-Internet-Security-Norton/IPS-extension-keeps-firefox-exe-from-ending/td-p/342560

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Norton IPS is apparently a known issue being mentioned in the KB articles:

What exactly is this IPS extension. I am currently using XPs with Norton's NIS (version 18.6 - it is a paid for subscription). I do have Intrusion Prevention active in NIS but I see no specific extension or program IPS. Is this some optional additional software?

I did find an explanation but from 2009

I am NOT using the Norton Toolbar etc. is it these components that are causing the problem i.e safe search etc.

I am not having problems with firefox hanging or continuing, despite using NIS. There is a bug on this https://bugzilla.mozilla.org/show_bug.cgi?id=548945 but that does not seem to have got very far in confirming or resolving the issue. I imagine Norton have a very large userbase and it seems unlikely that the basic NIS is itself incompatible with Firefox.