I keep receiving this message when I run mozilla firefox for win7 "what happened:TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined"
Whenever I open Firefox... an error pop up window appears with this message "what happened:TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined"
Chosen solution
This issue can be caused by an extension that isn't working properly.
Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).
- Don't make any changes on the Safe mode start window.
- https://support.mozilla.com/kb/Safe+Mode
If it does work in Safe-mode then disable all extensions and then try to find which is causing it by enabling one at a time until the problem reappears.
- Use "Disable all add-ons" on the Safe mode start window to disable all extensions.
- Close and restart Firefox after each change via "File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit")
In Firefox 4 you can use one of these to start in Safe mode:
- Help > Restart with Add-ons Disabled
- Hold down the Shift key while double clicking the Firefox desktop shortcut (Windows)
Read this answer in context 👍 5
All Replies (3)
Suluhisho teule
This issue can be caused by an extension that isn't working properly.
Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).
- Don't make any changes on the Safe mode start window.
- https://support.mozilla.com/kb/Safe+Mode
If it does work in Safe-mode then disable all extensions and then try to find which is causing it by enabling one at a time until the problem reappears.
- Use "Disable all add-ons" on the Safe mode start window to disable all extensions.
- Close and restart Firefox after each change via "File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit")
In Firefox 4 you can use one of these to start in Safe mode:
- Help > Restart with Add-ons Disabled
- Hold down the Shift key while double clicking the Firefox desktop shortcut (Windows)
Many thanks. It's solved. Cheers!
You're welcome