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After Updating and loading message windw apears "TypeError: Components.classes[cid] is undefined" why and what to do?

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  • Last reply by sergrop

sergrop
sergrop
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After upgrading to Firefox 6.0 after opening a small message window error opens with the message TypeError: Components.classes[cid] is undefined

After upgrading to Firefox 6.0 after opening a small message window error opens with the message TypeError: Components.classes[cid] is undefined

Chosen solution

This issue can be caused by an extension that isn't working properly.

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

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cor-el
cor-el
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Chosen Solution

This issue can be caused by an extension that isn't working properly.

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

sergrop
sergrop Question owner
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Thanks cor-el I solved the problem The offender was "OneClick YouTube Downloader 1.07" I removed it and FireFox works OK