What is the antivirus? Some, like AVG/Avast, block connections in recent cases. Run Windows in safe mode to test the effect of startup apps like antivirus.

If you only have gmail accounts, changing the TLS settings is unnecessary.

I have ESET anti virus. Crazy thing though is I can not log in in safe mode. My pin doesn't work (yes, I started with networking.) I tried my password for Microsoft and that doesn't work either. I then wanted to change my pw to another email address (their 2 part authentication) and I have to wait 30 days. Everything was fine until this darn TB update. I hate going to google.com to get my mail.

I have ESET and tried starting in safe mode. My pin and password was not accepted. Since all my saved emails in TB are on line at googlemail will deleting TB and downloading a previous version solve my problem?

Disable the email protection in ESET:

https://help.eset.com/emsl/7.0/en-US/idh_config_emon_clients.html

Gmail will work in the current TB if antivirus blocking is disabled. That won't disable the real-time background scan that protects against opening infected attachments.

Disabled email protection in ESET and still not working. Went to Google and tweaked according to their suggestions and still not working. It really is TB as the web client is working and I can access, send and receive emails. One post in Google suggested removing Gmail from TB and reinstalling it. Will try this before removing TB. Thanks for your attempts to help.

Just for giggles I tried Outlook (which I do not like) and my gmail works. What to do, what to do...

I have ESET and tried starting in safe mode. My pin and password was not accepted. Since all my saved emails in TB are on line at googlemail will deleting TB and downloading a previous version solve my problem?

Probability is high that ESET is causing your problems. According to their forums, you should temporarily disable SSL until they solve the problem per https://support.eset.com/en/kb3126-disable-ssl-filtering-in-eset-windows-products?ref=esf - the problem is being reported by dozens of users https://forum.eset.com/topic/26517-problems-with-thunderbird-and-imaps/ https://forum.eset.com/discover/

Thank you Wayne, it worked!

I just moved to Win 10 & downloaded the latest version of TB after using it successfully on Win 7 I copied all the settings from TB on the win 7 computer to the Win 10 pro computer

I have WASTED lots of time getting TB configured to connect to google mail and sbcglobal.mail

I have read thru lots of posts by users with similar issues. Not one solution works. WHY, in the 22nd year of the 21 century is it so difficult to do something that should be simple

Here are the current settings:

server: imap.googlemail.com

Connection : SSL/TSL Authorization: OAuth2 Port: 993 (default) Outgoing: smtp:google.mail.com Connection: SSL/TSL Authorization: OAuth2 Port: 465

NOW please tell me what is wrong with these settings

once I get the gmail settings working I will try to get the sbcglobal settings working I await a response

Here is more info : Disable AV/FW/SS mail-protection option, unless it has option to add Exception. in Exception list add mail-server name/address. Make sure the option "Allow AV to Quarantine email" is selected inside TB, and make sure your AV/SS is set to Scan all files on access.