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Mac Latest Firefox, all websites showing insecure connection

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  • 46 have this problem
  • 11 views
  • Last reply by Ncnative

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I am getting the message that the connection is insecure on every site. I could not even go to the Mozilla site and am using Safari. I went to the about: config page and changed the insecure connection to false. Still cannot get on any site. I am on the latest Firefox and I tried the advice for changing Avast preferences, and it must be for the older version because my version does not allow me to change anything pertaining to HTTP - there was an Ipv option... The only other add ons I have are Adblock and Pinterest. It was fine last night - this morning I can't get on any site.

I am getting the message that the connection is insecure on every site. I could not even go to the Mozilla site and am using Safari. I went to the about: config page and changed the insecure connection to false. Still cannot get on any site. I am on the latest Firefox and I tried the advice for changing Avast preferences, and it must be for the older version because my version does not allow me to change anything pertaining to HTTP - there was an Ipv option... The only other add ons I have are Adblock and Pinterest. It was fine last night - this morning I can't get on any site.

Chosen solution

Let's assume the problem is that Firefox's requests are being intercepted and filtered by the Avast Web Shield feature. In order to check the contents of HTTPS connections, Avast needs to generate fake site certificates. Usually Avast will add the signing certificate it uses to generate fake site certificates to a Firefox settings file for you automatically. However, if that file is removed (either by hand or using the Refresh feature), it needs to be added again. I don't know if you can find a function within Avast to trigger that, or whether it would happen at your next Windows startup. If those don't work, there's probably a way to do it manually.

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It could be an issue with Avast, or possibly something else.

The "Your connection is not secure" page generally has an "Advanced" button to get more technical information, including an ERROR_CODE that helps us diagnose the problem more specifically. Could you dig that out? Meanwhile:

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The Mozilla certificate is listed on the Avast site, as are others like Google, etc. I've had Avast for some time. I did trash the Mackeeper app so I don't know if that could be causing the problem or not? I don't see any extensions or plug ins that would be blocking the site. This is what I got when I tried Yahoo -

www.yahoo.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported.

Error code: SEC_ERROR_UNKNOWN_ISSUER

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Chosen Solution

Let's assume the problem is that Firefox's requests are being intercepted and filtered by the Avast Web Shield feature. In order to check the contents of HTTPS connections, Avast needs to generate fake site certificates. Usually Avast will add the signing certificate it uses to generate fake site certificates to a Firefox settings file for you automatically. However, if that file is removed (either by hand or using the Refresh feature), it needs to be added again. I don't know if you can find a function within Avast to trigger that, or whether it would happen at your next Windows startup. If those don't work, there's probably a way to do it manually.

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I went back and first tried to use Firefox in private mode - nothing changed - so I refreshed Firefox. When I did that, a message from Avast popped up saying that it had been updated. Now it seems to be working - even though the Avast site had Mozilla as tagged not to scan, so not sure what happened, but removing the add ons seemed to do the trick.