TB will not ask for a password

That typically means there's a problem to connect to the server in the first place, so that Thunderbird doesn't even get to the point to prompt you for the password. See https://support.mozilla.org/kb/cannot-send-messages

Thank you for your response. I have been through the list several times without making any progress. Have tried every thing suggested once to many times. This started three weeks ago, but TB was only out for a day at a time, then worked for a week - now out four days.

You should contact your email provider.

Good idea. I did, but they do not understand English. It seems to me that I have to get an outbound password into TB before I can do much with ATT. Without a password in TB I can not get to the ATT server - can I?

Lberty7 said

Without a password in TB I can not get to the ATT server - can I?

Yes you can. Connection work by Thunderbird going out to the server it is told to and asking to get or send mail.

After the conversation starts the server asks for a password, which Thunderbird either supplies if it has it or ask for it. My guess is you have an anti virus firewall blocking a new version of Thunderbird from accessing the internet at all. This is very common with the anti virus firewalls. Quite uncommon with hardware firewalls, such as are built into almost all internet modems/routers

Thank you Matt. I have turned off Defender several times. Have TB listed as an exception to pass the firewall. Does not seem to make any difference. Still will not ask for a password. No other AV or firewall.

TB turned itself off three or four different days about three weeks ago.. Recovered ability to send emails without any intervention. Just waited. This round I deleted the outbound password after 24 plus hours in an effort to restore outgoing email - now cannot get TB to ask for PW.

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