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Just upgraded to firefox 4 and it won't start but it says it's running.

  • 6 replies
  • 91 have this problem
  • 9 views
  • Last reply by foxoffire

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I just recently upgraded to firefox 4 and it won't work. I was enjoying the lastest update on firefox 3 and it was working fine, but when i upgraded to 4, the problems started. Every time i click on the icon, the mouse turns into the loading wheel for a few seconds and then goes back, but firefox doesn't load up. Nothing happens. I have tried restarting the computer, but that does nothing. I then tried uninstalling it, but it says firefox is still running so it can't uninstall. Even after restarting my computer, it still says it's running. I have tried everything, but it just won't start, and I can't do anything because it claims to still be running.

I just recently upgraded to firefox 4 and it won't work. I was enjoying the lastest update on firefox 3 and it was working fine, but when i upgraded to 4, the problems started. Every time i click on the icon, the mouse turns into the loading wheel for a few seconds and then goes back, but firefox doesn't load up. Nothing happens. I have tried restarting the computer, but that does nothing. I then tried uninstalling it, but it says firefox is still running so it can't uninstall. Even after restarting my computer, it still says it's running. I have tried everything, but it just won't start, and I can't do anything because it claims to still be running.

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I had this same issue when I installed this morning. After installation, the browser locked up my whole computer while I was browsing personas and I was forced to do a hard reset. Afterwards, I got the same error as you. My computer informed me that the files for Firefox may be corrupt, so I did a check disk on my restart and it resolved the issue. Firefox now opens just fine, however... it's not allowing me to leave the homepage. Address bar and bookmarks and links are not working. Can't seem to win.

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I have exactly the same problem! I can't install or uninstall and have lost my previous version. Does anyone know which files would need to be removed manually to allow us to reinstall the old version?

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by going to the processes tab in the task manager, i have been able to stop firefox and uninstall it. i have since reinstalled firefox 3 which is working great. i wonder what's wrong with 4...

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I just had a similar problem and it reminded me of trying to install a logitech wireless mouse a while back. Nothing I could do to make it recognize the driver... until I ran across a website that told me that antivirus and firewalls might prevent it. So... AVG Free just updated itself earlier today... FF4 would only startup once after reboot, then start and show in task mgr but no window(s)... Uninstalled AVG new version. FF4 starts up every time. Reinstalled older version of AVG Free and now everything seems to be OK again. Hope this helps!

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Thank you cor-el, but I read those before posting and those didn't seem to help much.

Hereforquickone: that could be. I have the new norton security, not sure how the firewalls are on that, but I've been using chrome since posting this, so no point in me changing my antivirus now. The only reason i wanted to keep firefox was for my bookmarks and those disappeared like a week after i went back to firefox 3.