Join the Mozilla’s Test Days event from 9–15 Jan to test the new Firefox address bar on Firefox Beta 135 and get a chance to win Mozilla swag vouchers! 🎁

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Rohkem teavet

How to get rid of an error message?

  • 2 vastust
  • 20 on selline probleem
  • 3 views
  • Viimati vastas lawandra

more options

I downloaded the new Firefoxy4, and each time I open it I get a message window that says: Type Error:Components.classes[@mozilla.org/extension/manager:1] is undefined. and asks to press the OK button. When pressed Firefox 4 opens. How do I get rid of the error message?

I downloaded the new Firefoxy4, and each time I open it I get a message window that says: Type Error:Components.classes[@mozilla.org/extension/manager:1] is undefined. and asks to press the OK button. When pressed Firefox 4 opens. How do I get rid of the error message?

Valitud lahendus

This is probably due to an add-on that is not compatible with Firefox 4. For details of how to troubleshoot that see https://support.mozilla.com/kb/Troubleshooting+extensions+and+themes

Loe vastust kontekstis 👍 2

All Replies (2)

more options

Valitud lahendus

This is probably due to an add-on that is not compatible with Firefox 4. For details of how to troubleshoot that see https://support.mozilla.com/kb/Troubleshooting+extensions+and+themes

more options

Thanks TonyE That worked a treat. Cheers Lawandra