Can't send Bcc anymore
I've used Thunderbird for many years, problem free. Suddenly, when trying to send a Bcc email, I get this:
Sending of the message failed.
The message could not be sent using Outgoing server (SMTP) smtp.cox.net for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again.
Alla svar (1)
Content is usually just text but in the past I've never been restricted in any way as to Bcc content. I have removed all anti-virus programs except Windows Defender and it has been that way for at least a year. Yes, it says 'True'.