I can't send emails from my account.
I can't send emails from my personal domain account (suzanne@suzannekosowitz.com) on Thunderbird. The webmail works online, just not through Thunderbird. I can still receive emails through Thunderbird,
Alla svar (1)
Start here: https://support.mozilla.org/en-US/kb/cannot-send-messages and then come back if that doesn't take care of it and supply Operating System and TB version.