IMAP Thunderbird Gmail import
Set up IMAP
Step 1: Check that IMAP is turned on
- On your computer, open Gmail.
- In the top right, click Settings .
- Click Settings.
- Click the Forwarding and POP/IMAP tab.
- In the "IMAP access" section, select Enable IMAP.
Step 2: Set Google account Security
- Go to Google Account
- Securuty > Less secure app access
- Click [Turn on access (not recommended)]
- Allow less secure apps: OFF -> ON
Step 2: Tunderbird settings in your email client
Try use Normal Password Authentication instead of OAuth2