I am using Thunderbird for several different emails. several gmail accounts and an outlook account, and also my work emails. Gmail and outlook works fine. The work emails have stopped working. When sending it says "Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) mail.cyriousmetalworks.com was lost in the middle of the transaction. Try again." This has been a working email with Thunderbird for years now. I have contacted my email server and they say its not on their end. Any help will be appreciated. Thanks