Hi Ron,
Please accept our apologies for the inconvenience caused.
First of all, we request you to share us a screenshot of the certificate error you've been receiving.
You can post the screenshot here in your topic. Click on Answer & then click on the Image [mountain symbol] & follow the instructions.
Secondly, we request you to temporarily disable the individual shields/components of your AVG Internet Security & check which shield/component is causing the issue.
Refer to this article to temporarily disable the individual shields/components of your AVG Internet Security.
Keep us updated.

I disabled the entire AVG suite and still got the error message. Meaning, I disabled, rebooted and then tried again. Chome and Edge did not work, IE started working. I didn't test AVG Secure Brower with it disabled.
Thank you for sharing the screenshot, Ron.
Since the issue still persists after disabling your AVG Internet Security, could you share us the screenshot of the Internet Explorer window showing that AVG is the one causing the certificate error?
Also, could you temporarily disable your AVG Secure VPN, AVG AntiTrack programs & check for the issue?
Keep us updated.
Hi Ron,
Please accept our apologies for the inconvenience caused.
First of all, we request you to share us a screenshot of the certificate error you've been receiving.
You can post the screenshot here in your topic. Click on Answer & then click on the Image [mountain symbol] & follow the instructions.
Secondly, we request you to temporarily disable the individual shields/components of your AVG Internet Security & check which shield/component is causing the issue.
Refer to this article to temporarily disable the individual shields/components of your AVG Internet Security.
Keep us updated.