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Can't connect after reinstalling Firefox - related to Avast

  • 2 replies
  • 8 have this problem
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  • Last reply by aviavi

aviavi
aviavi
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After reinstalling Firefox, I get "invalid security certificate....Error code: SEC_ERROR_UNKNOWN_ISSUER" messages for every web page I try to load. It is related to the Web Shield being enabled in Avast. Firefox works when Web Shield is disabled.

However, the steps Mozilla/Firefox lists here https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER to fix the problem do not work, and the functions are not even in the current version of Avast.

Not sure what to do.

After reinstalling Firefox, I get "invalid security certificate....Error code: SEC_ERROR_UNKNOWN_ISSUER" messages for every web page I try to load. It is related to the Web Shield being enabled in Avast. Firefox works when Web Shield is disabled. However, the steps Mozilla/Firefox lists here https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER to fix the problem do not work, and the functions are not even in the current version of Avast. Not sure what to do.

Chosen solution

Avast or any A/V program will update automatically and sometimes they will break or block sites without telling you. And since it's every page I would suspect the A/V is causing the problem. As you noted turning off Web Shield stops it so my advice find a better A/V that doesn't think it knows better then you know your web browsing habits.

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WestEnd
WestEnd
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Chosen Solution

Avast or any A/V program will update automatically and sometimes they will break or block sites without telling you. And since it's every page I would suspect the A/V is causing the problem. As you noted turning off Web Shield stops it so my advice find a better A/V that doesn't think it knows better then you know your web browsing habits.

aviavi
aviavi Question owner
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Thanks for the reply. What I don't understand is why Avast would start doing this after reinstalling Firefox, and why other browsers are not affected. Firefox was working fine with Avast before. Now I can't even reach the Mozilla site with Firefox.