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After updating Firefox I am getting this message any time I do anything "Exc in ev handl:Error: Bad NPObject as private data"

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This error happens each time I use Mozilla. especially when I click on an extension or try to work in any of my e-mail accounts (Yahoo, Gmail, or RCN). Sometimes I am able to continue by just clicking OK and other times it prevents me from completing my task. This started happening right after I downloaded and installed your latest version of Firefox. I see others are having the same problem. Error message is "Exc in ev handl:Error: Bad NPObject as private data"

This error happens each time I use Mozilla. especially when I click on an extension or try to work in any of my e-mail accounts (Yahoo, Gmail, or RCN). Sometimes I am able to continue by just clicking OK and other times it prevents me from completing my task. This started happening right after I downloaded and installed your latest version of Firefox. I see others are having the same problem. Error message is "Exc in ev handl:Error: Bad NPObject as private data"

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That issue can be caused by the McAfee Site Advisor extension


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