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When I click on firefox to open in my Mac, an error shows up: plug-in object Type error: id is undefined. When I click on the OK button, firefox opens. This never happened in FF 3. What is this?

  • 3 replies
  • 6 have this problem
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  • Last reply by cor-el

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Also when I am in a site, such as an account, and click on a highlighted link, I get another error, {Javascript Application] can't create mcafee plug-in object: Type Error: components. classes [cid] is undefined. The only mcafee I had on my computer was the secure search and I uninstalled it, but I still get this message. When I click on the OK button with the error message, then the link opens up.

Also when I am in a site, such as an account, and click on a highlighted link, I get another error, {Javascript Application] can't create mcafee plug-in object: Type Error: components. classes [cid] is undefined. The only mcafee I had on my computer was the secure search and I uninstalled it, but I still get this message. When I click on the OK button with the error message, then the link opens up.

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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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Thanks that fixed it, it was mcafee site advisor and it corrected when I disabled it. Does this mean I can't ever use it with FF4?

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You're welcome.

You will have to wait for McAfee to release an update that fixes this issue. I've seen quite a few threads about this issue, so it happens more often.