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can't create mcafee plug-in object: TypeError: Components.classes[cid] is undefined

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I updated to Firefox 4.0 and ever since then, I get this message when I try to open Firefox:

can't create mcafee plug-in object: TypeError: Components.classes[cid] is undefined

I have a Mac and have McAfee protection for Mac. This problem did not happen before I updated Firefox. Once I click on "OK" Firefox opens.

I updated to Firefox 4.0 and ever since then, I get this message when I try to open Firefox: can't create mcafee plug-in object: TypeError: Components.classes[cid] is undefined I have a Mac and have McAfee protection for Mac. This problem did not happen before I updated Firefox. Once I click on "OK" Firefox opens.

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This issue is most likely caused by a McAfee extension that isn't working properly and you will have to disable the extension that causes it.

You can also check if there is an update available from McAfee that fixes this problem.

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How do I do that? I've tried to find a fix on McAfee's site, but to no avail.