his message is displayed on Firefox start-up:
Box title is "JAVA Script Application"
what happened:TypeError: components.classes['@mozilla.org/extensions/manage
That is an indication that you have an incompatible add-on. Follow the procedure in the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article to identify the culprit.
Foxit Toolbar is a likely suspect if you started receiving this message recently. The error stopped happening for me the instant I disabled this add-on.
Your above posted system details show outdated plugin(s) with known security and stability risks.
Update the Java plugin to the latest version.
Update the Flash plugin to the latest version.
This could also be caused by the Ask Toolbar. Can you disable that and try again?
If you have the Ask Toolbar installed under Firefox 4.0b1+ it will give this error. The toolbar lies in its install manifest to say it is compatible with up to Firefox 5.* (you heard me) thus you'll need to disable or uninstall it. A blocklist request is pending...
It happens to me when I installed a new release of skype (5.5). Yust disable the plugin and the problem will fixed.
I concur that the problem is an add-on that is incompatible with FF5. Disable it and reboot. Problem solved.
Thank u very much for your post, cuz u were right on the money! After chasing the problem for hours last nite, installing, uninstalling etc.; I stumbled across your post here thankfully. Thank u once again!