Hi, like other users on this help service, I recently lost the ability to send smtp gmails on one specific gmail account, but receiving emails was OK. Every attempt to send brought a "send failed - enter new password" dialog box. I looked at a great number of "solutions" before I found one which almost worked, but I have modified/clarified it and post it here for others to try. First off, look at passwords in Settings, and check that you have an 0Auth2 password - very long and not anything you chose. Then go to Server settings, scroll down the left hand pane past all the accounts listed until you find "Outgoing Server (SMTP) and click on it. This lists your outgoing SMTP accounts. Highlight the one for the account which is not sending and click on "Edit" Change the authentication method to 0Auth2. OK your way back. Now go back to your displayed passwords and copy the 0Auth2 password from the incoming password box and paste it in the SMTP password box for the problem account. Now close TB and restart. When I did all this, it began to send emails again. Hope it helps someone else.