Problems with firefox 58

What if the problem occurs on Win 10?

Hello Robert,
Thank you for reaching us with your concerns. This issue is most likely caused because we are adding AVG certificate into the Firefox. We would request you to try and add the AVG certificate to Firefox manually to resolve the issue.
To start with, it is necessary to obtain a copy of the certificate.
This can be found with Keychain Access with Keychain "login" and category "Certificates". Search for "avg". You should find "AVG trusted CA". Select it and export it from the menu bar under "File" then "Export Items…". Save it somewhere accessible.
Now, the certificate needs to be added to Firefox's certificate manager.
Open Firefox's Preferences > Privacy & Security tab. Scroll down to Security > Certificates. Open "View Certificates…". Click on "Authorities" then "Import…". Import "AVG trusted CA" and trust it to "identify websites". You can select "identify mail users" if you want.
Best regards,
Alok.

As of 2-1-18 firefox stopped connecting to any site with the same error.
Just checking to see if there is an issue with firefox and AVG.
Safari and Google Chrome are working but Firefox gives error unable to make secure connection secure website configured wrong

What if the problem occurs on Win 10?

Hello Robert,
Thank you for reaching us with your concerns. This issue is most likely caused because we are adding AVG certificate into the Firefox. We would request you to try and add the AVG certificate to Firefox manually to resolve the issue.
To start with, it is necessary to obtain a copy of the certificate.
This can be found with Keychain Access with Keychain "login" and category "Certificates". Search for "avg". You should find "AVG trusted CA". Select it and export it from the menu bar under "File" then "Export Items…". Save it somewhere accessible.
Now, the certificate needs to be added to Firefox's certificate manager.
Open Firefox's Preferences > Privacy & Security tab. Scroll down to Security > Certificates. Open "View Certificates…". Click on "Authorities" then "Import…". Import "AVG trusted CA" and trust it to "identify websites". You can select "identify mail users" if you want.
Best regards,
Alok.