Website certificate errors

Hello Bruce,
I understand the inconvenience caused. Could you share a screenshot of the error message to assist you further?
You can post the screenshot here on your topic. Click on 'Answer' & then click on the 'Image' [mountain symbol] & follow the instructions.
Best regards,
Alok.

every https website I visit comes up with a certificate error. 

I downloaded the certificate, here is the issuer
CN = AVG Web/Mail Shield Root
O = AVG Web/Mail Shield
OU = generated by AVG Antivirus for SSL/TLS scanning

If I add a URL to the exceptions list it starts working

Hello Bruce,
I understand the inconvenience caused. Could you share a screenshot of the error message to assist you further?
You can post the screenshot here on your topic. Click on 'Answer' & then click on the 'Image' [mountain symbol] & follow the instructions.
Best regards,
Alok.