Can receive but not send emails with Gmail account
Just thought I would post this information, as I had a hard time finding it. I just migrated my account to a new PC. My Hotmail account worked with the default settings, but my Gmail wouldn't connect.
This was due to the 2-factor authentication with Google. I could have disabled that feature, but I want to keep it.
Here's how I changed the settings: > Menu button - 3 lines in the top right > Account Settings > Server Settings > Authentication method : changed to OAuth2 > Follow the prompts in the pop-up to authorize google access. This will require secondary confirmation, mine came through my phone, but it could be via email.
After this I could receive mail. Later I discovered I couldn't send mail via the following error:
Sending of the message failed. Unable to authenticate to Outgoing server (SMTP) smtp.googlemail.com. Please check the password and verify the 'Authentication method' in 'Account Settings | Outgoing server (SMTP)'.
I did the following to fix: > Menu button - 3 lines in the top right > Account Settings > Select the account xxxxx@gmail.com > at the bottom - Outgoing Server (SMTP) hit the "Edit SMTP server" button on right > Select OAuth2 No further verification was needed after that and I was able to send and receive.
Alla svar (1)
The use of oAuth2 is the default for all newly added accounts to Thunderbird and has been for a number of years.
The fact your account is using a googlemail server name may cause issues with oAuth. Google deprecated those server names about a decade ago, just about when they exited the beta program. Correct server names are gmail servers. pop.gmail.com, imap.gmail.com, smtp.gmail.com.
The config file containing the setting Thunderbird uses when a gmail account is configured is here https://autoconfig.thunderbird.net/v1.1/gmail.com