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500 Internal Server Error: An unknown error has occurred

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  • 66 have this problem
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  • Last reply by aquarin

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When I open my browser, it immediately displays this error message. No matter what web site I navigate to, I get this message.

I have no problems with Internet Explorer, so I know this is limited to Firefox.

I've been gone for the past 5-6 days and just got home. It worked fine 5-6 days ago. The only change I noticed was that it installed an update to AdBlock Plus. Not sure why that would matter, but I uninstalled AdBlock Plus just to be sure. It didn't help- error is still occurring.

I also tried uninstalling and re-installing Firefox, but that didn't help either.

Anyone know why this is happening and what I can do to fix it?

Thanks!

When I open my browser, it immediately displays this error message. No matter what web site I navigate to, I get this message. I have no problems with Internet Explorer, so I know this is limited to Firefox. I've been gone for the past 5-6 days and just got home. It worked fine 5-6 days ago. The only change I noticed was that it installed an update to AdBlock Plus. Not sure why that would matter, but I uninstalled AdBlock Plus just to be sure. It didn't help- error is still occurring. I also tried uninstalling and re-installing Firefox, but that didn't help either. Anyone know why this is happening and what I can do to fix it? Thanks!

All Replies (1)

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It seems the same error was posted several times in this forum.

See this post for more information:

https://support.mozilla.com/en-US/questions/780053#answer-135866

I resolved the issue by removing the "Relevent Knowledge" add-on. Now Firefox works normally.