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Firefox was recently updated to 3.6.6 and now repeatedly becomes nonresponsive. How do I fix this?

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Firefox auto updated to v 3.6.6 and now it repeatedly stops responding. I have to open task manager and end the program numerous times a day. This did not happen in the previous version.

User Agent

Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; GTB6.3; WinNT-PAI 07.08.2009; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)

Firefox auto updated to v 3.6.6 and now it repeatedly stops responding. I have to open task manager and end the program numerous times a day. This did not happen in the previous version. == User Agent == Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; GTB6.3; WinNT-PAI 07.08.2009; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)

All Replies (2)

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Microsoft .NET Framework Assistant 1.1 is not compatible with firefox 3.6.6

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Firefox 3.6.4 and 3.6.6 use a process called, "plugin-container.exe" which was using up most of my CPU when I opened up multiple tabs that contained Adobe Flash files, and caused Firefox to lock up.

My solution was to use Firefox 3.5.10 which you can get from the Mozilla website at http://www.mozilla.com/en-US/firefox/all-older.html I am using Adobe Flash 10.1.53.64 without any problem in this version of Firefox. Check the release notes, I believe it contains all the latest security fixes in "Firefox 3.6.4".

Hopefully, they will fix Firefox 3.6 in the next version (e.g. Firefox 3.6.7), until then you should probably use "Firefox 3.5.10".