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.

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

Issue between Thunderbird and Comcast email?

  • 3 cavab
  • 1 has this problem
  • 18 views
  • Last reply by sfhowes

more options

I've been using Thunderbird and Comcast forever, never a problem. Last week Thunderbird quit sending e-mails. I've changed all passwords and re-checked SMTP settings and uninstalled and re-installed Thunderbird and nothing works. I can not fix this. Please help. This is the error message:

An error occurred while sending mail: The mail server sent an incorrect greeting: resomta-po-10v.sys.comcast.net resomta-po-10v.sys.comcast.net Excessive failed authentication, ESMTP server temporarily not available.

I've been using Thunderbird and Comcast forever, never a problem. Last week Thunderbird quit sending e-mails. I've changed all passwords and re-checked SMTP settings and uninstalled and re-installed Thunderbird and nothing works. I can not fix this. Please help. This is the error message: An error occurred while sending mail: The mail server sent an incorrect greeting: resomta-po-10v.sys.comcast.net resomta-po-10v.sys.comcast.net Excessive failed authentication, ESMTP server temporarily not available.

All Replies (3)

more options

When you changed passwords, did you delete the old ones in Saved Passwords in Options, restart TB, then enter the new passwords when prompted? Is the outgoing server smtp.comcast.net on 465, SSL/TLS, normal password authentication? What is the antivirus and its settings for scanning email?

more options

Yes. I did everything listed above.

My antivirus is Norton.

more options

You probably want to add the TB profile folder as an exclusion or disable whatever setting in Norton applies scanning to outgoing mail. You may also have to disable scanning of secure connections.