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gmail authentication failures

SuMo Bot

I had to migrate from an older version of outlook due to Google changing security requirements in May 2022. I was able to setup my 3 accounts, 2 gmail and 1 outlook on Thunderbird and it worked for a few days. It broke again on the 15th for the 2 gmail accounts and I cannot get or send email. I keep getting authentication error connecting to imap.gmail.com. I have thunderbird running on another computer with no issues. I have done some compare settings between desktops (different rooms) and I cannot figure out why I cannot connect with this other computer.

I had to migrate from an older version of outlook due to Google changing security requirements in May 2022. I was able to setup my 3 accounts, 2 gmail and 1 outlook on Thunderbird and it worked for a few days. It broke again on the 15th for the 2 gmail accounts and I cannot get or send email. I keep getting authentication error connecting to imap.gmail.com. I have thunderbird running on another computer with no issues. I have done some compare settings between desktops (different rooms) and I cannot figure out why I cannot connect with this other computer.

All Replies (1)

When creating the gmail accounts did you set up to use Authentication Method: OAuth2 for both incoming and outgoing smtp or is Authentication Method set for 'Normal Password? Did you set up to allow cookies in Thunderbird ? When creating the gmail accounts did you get prompted to logon in a google window to allow Thunderbird access ?

In Menu icon > Preferences > Privacy & Security Are the google cookies saved ? What do you see in the Saved PAsswords? do you see the oauth tokens for the gmail accounts? Do you see lines with imap:// and smtp:// that have the normal password saved ?

Do you use a VPN ? If yes then switch it off. Note: I use Norton 360 and it updated and auto installed and switched on VPN without my knowledge, so do check to see if you have a VPN suddenly operating.

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