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How to fix JavaScript App Type error: Components classes'@mozilla.org/extensions/manager;1' is undefined

  • 3 replies
  • 161 have this problem
  • 3 views
  • Last reply by Xircal

Azmax
Azmax
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Every time FF4.0.1 is opened the error message shows and must nbe closed before the FF screen shows. I've reloaded FF4.0.1 in hopes some code was missing, but no change....the Java Script Application error message still shows?

Every time FF4.0.1 is opened the error message shows and must nbe closed before the FF screen shows. I've reloaded FF4.0.1 in hopes some code was missing, but no change....the Java Script Application error message still shows?

Chosen solution

See http://support.mozilla.com/en-US/questions/749513

Read this answer in context 👍 5

All Replies (3)

Xircal
Xircal
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Chosen Solution

See http://support.mozilla.com/en-US/questions/749513

Azmax
Azmax Question owner
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Following the ideas in the prior FAQ cited, went to the FF Troubleshooting extensions and themes & followed it down through disabling extensions. The Ask toolbar turned out to be the culprit even though in was not on the FF screen.

Xircal
Xircal
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I noticed you have My Web Search installed which might also cause you problems at some time in the future. I'd avise you to disable that too via Add-ons | Plugins. See http://en.wikipedia.org/wiki/My_web_search

You also need to update Flash via http://get.adobe.com/flashplayer/ Details of the vulnerability in the version you have installed at the moment can be seen here: http://www.adobe.com/support/security/advisories/apsa11-02.html