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After downloading 4.0 I get this message: JavaScript application can't create mcafee plug-in object: TypeError: components.classes[cid] is undefined

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  • Last reply by mrbillshaw

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I finished downloading Firefox 4.o to my Mac OS.X. When I try to open a website I get the message: [JavaScript Application] can't create mcafee plug-in object: TypeError: Components.classes[cid] is undefined If I click the OK button, the site opens, but without the McAfee alert at the bottom of the window. I had just downloaded 3.6.16, and got box suggesting download version 4.0 for better security, but that seems to be where the problem is!

I finished downloading Firefox 4.o to my Mac OS.X. When I try to open a website I get the message: [JavaScript Application] can't create mcafee plug-in object: TypeError: Components.classes[cid] is undefined If I click the OK button, the site opens, but without the McAfee alert at the bottom of the window. I had just downloaded 3.6.16, and got box suggesting download version 4.0 for better security, but that seems to be where the problem is!

Chosen solution

That indicates that an add-on you are using is not compatible, considering the other errors it is possibly the McAfee add-on. To confirm what add-on is causing this use the procedure in this link - https://support.mozilla.com/kb/Troubleshooting+extensions+and+themes

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Chosen Solution

That indicates that an add-on you are using is not compatible, considering the other errors it is possibly the McAfee add-on. To confirm what add-on is causing this use the procedure in this link - https://support.mozilla.com/kb/Troubleshooting+extensions+and+themes

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I tried the troubleshooting+extensions solution, deleting the McAfee extension. Firefox is now up and running. Thank you!

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In my case it was Billeo - I got the error on an HP Laptop with Windows 7 64bit but not on an iMac with the same OS under VMware Fusion. May be some sort of hardware related problem.