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I get an error msg when firefox 4 opens up " Components, classes @ Mozilla.org/extensions/manager 1, is undefined "

  • 2 replies
  • 8 have this problem
  • 14 views
  • Last reply by Deano2u2

Deano2u2
Deano2u2
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I upgraded to Firefox 4 and when I open it, I get the error message. It has a "OK" button on the error message and if I click on the OK message, Firefox will open up fine and seems to work ok. Once in awhile when searching the web and I click on a link, the error message comes up again, and when I click on the OK button it brings up the link I clicked on. I un-installed Firefox 4, and reinstalled Firefox 3.6.8. Everything works great and no error message. I then installed Firefox 4 again and I get the error message again. I am running Windows Vista, Premium Home, and I have 3 Gigs of memory. I dont have any problems with other Browsers, only Firefox 4.

I upgraded to Firefox 4 and when I open it, I get the error message. It has a "OK" button on the error message and if I click on the OK message, Firefox will open up fine and seems to work ok. Once in awhile when searching the web and I click on a link, the error message comes up again, and when I click on the OK button it brings up the link I clicked on. I un-installed Firefox 4, and reinstalled Firefox 3.6.8. Everything works great and no error message. I then installed Firefox 4 again and I get the error message again. I am running Windows Vista, Premium Home, and I have 3 Gigs of memory. I dont have any problems with other Browsers, only Firefox 4.

All Replies (2)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the add-ons is causing the problem (switch to the DEFAULT theme: Tools > Add-ons > Appearance/Themes).

  • Don't make any changes on the Safe mode start window.

See:

Deano2u2
Deano2u2 Question owner
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Thanks a lot. I entered FireFox in the Safe Mode, and it worked perfectly. No Error Message. It stated that Firefox disables all add on's when you enter in the safe mode.I went into the DEFAULT theme and all the add-on's listed were disabled. I exited out of the Safe Mode and restarted Firefox. It worked fine and opened up without any error message. I didnt make any changes, but it works fine now, So thanks a bunch. Deano2u2