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Installed Firefox 4 on my Mac; getting error messages upon start up and when opening photos (i.e. ebay)

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I updated to Firefox 4 and now continuously receive error messages. One example is when I'm in Ebay and click on a photo to enlarge I get the following error message.

(JavaScript Application) can't create mcafee plug-in object: TypeError: Components.classes(cid) is undefined

Another example is upon start up of Firefox I receive an error message but I can't make it out since its half hidden on my desktop but I have to click "ok" in order to open up Firefox.

I'm barely learning how to use this Mac (a task in its self), but now I have these error messages? Can I just go back to my older version of Firefox to make these error messages go away?

Thanks, JR.

I updated to Firefox 4 and now continuously receive error messages. One example is when I'm in Ebay and click on a photo to enlarge I get the following error message. (JavaScript Application) can't create mcafee plug-in object: TypeError: Components.classes(cid) is undefined Another example is upon start up of Firefox I receive an error message but I can't make it out since its half hidden on my desktop but I have to click "ok" in order to open up Firefox. I'm barely learning how to use this Mac (a task in its self), but now I have these error messages? Can I just go back to my older version of Firefox to make these error messages go away? Thanks, JR.

All Replies (2)

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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the add-ons is causing the problem (switch to the DEFAULT theme: Tools > Add-ons > Appearance/Themes).

  • Don't make any changes on the Safe mode start window.

See:

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Thank you very, very much. This was my very first time trying to solve a technical issue on my Mac... your advice worked great. I disabled all the add-on apps and it solved my issue. Don't know if I should have disabled all but it seemed to work... Thanks again for the advice.