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Firefox cant find xpcom_core.dll. What do I do?

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  • 20 have this problem
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  • Last reply by cor-el

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Whenever it boots up to my yahoo page error message "cant find xpcom_core.dll".

What do I do to fix this problem?

Whenever it boots up to my yahoo page error message "cant find xpcom_core.dll". What do I do to fix this problem?

All Replies (1)

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The file xpcom_core.dll was last used in Firefox 2.0.0.x versions and is no longer present in current Firefox versions.
You seem to have a program or an add-on that is still looking for that file.


Your plugins list shows that you have the Mozilla ActiveX plugin installed and that might cause your problem.
The Mozilla ActiveX plugin is not compatible with Firefox 2 and 3 and you should remove it.

For instructions on how to remove the Mozilla ActiveX plugin see: http://kb.mozillazine.org/ActiveX