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Thunderbird no longer accessing Gmail

Thunderbird Privacy and security
Matt replied
northants1
northants1

Running TB 78.11.0 in Windows 10 21H1. Being running TB for years. Last couple of days no longer accessing Gmail when press Get Mail button get box saying Certificate not trusted and asking me to add a security exception. I have changed nothing in TB account settings or Gmail. Gmail messages accessable OK via web browser or iPad. Is anyone else seeing this, and any ideas of solution.

Running TB 78.11.0 in Windows 10 21H1. Being running TB for years. Last couple of days no longer accessing Gmail when press Get Mail button get box saying Certificate not trusted and asking me to add a security exception. I have changed nothing in TB account settings or Gmail. Gmail messages accessable OK via web browser or iPad. Is anyone else seeing this, and any ideas of solution.
Matt
Matt
  • Top 25 Contributor
Read this answer in context

Chosen Solution

I assume Avast support will be able to assist you in configuring their product to work.

All Replies (4)

Toad-Hall
Toad-Hall
  • Top 25 Contributor

That sounds like your Anti-Virus could be forcing you to see that message, so click on add exception.

You normally never store a certificate for Gmail in the server tab.

In Account Settings' for the gmail account, click on 'End-To-end Encryption'. 'Manage S/MIME Certificates; opens 'Certificate Manager' click on 'Authorities' tab. You should see 'Google Internet Authority G2' under 'GeoTrust Inc'.

Toad-Hall
Toad-Hall
  • Top 25 Contributor

If you are using AVAST: Make sure Avast is up to date. Then try manually adding certificate. You may need to remove the stored one first. https://support.avast.com/en-ww/article/Troubleshoot-invalid-email-certificate

Alternatively: Switch off the Avast mail shield https://support.avast.com/en-ww/article/Antivirus-shield-settings

Or accept as security exception.

northants1
northants1 Question owner

Thanks for information. I tried disabling Avast Mail Shield and problem disappeares. I also tried suggested path to export Mail Shield certificate from Avast and import into Thunderbird. This did not fix the issue.

Matt
Matt
  • Top 25 Contributor

Chosen Solution

I assume Avast support will be able to assist you in configuring their product to work.