This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

This thread was archived. Please ask a new question if you need help.

Can't send Bcc anymore

  • 41 replies
  • 5 have this problem
  • 1 view
  • Last reply by tiger-rka07

tiger-rka07
tiger-rka07
more options

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.

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.

All Replies (1)

tiger-rka07
tiger-rka07 Question owner
more options

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'.

  1. 1
  2. 2
  3. 3