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Authentication error using Thunderbird with Comcast / Xfinity email

  • 2 replies
  • 1 has this problem
  • 20 views
  • Last reply by Paul Gritt

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Using Thunderbird with Xfinity email, sending an email gets the below error message. I contacted Comcast and we went through troubleshooting and could not find any problems on their end. They suggested I contact Thunderbird support. Here is the error message: "Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: resomta-po-11v.sys.comcast.net resomta-po-11v.sys.comcast.net Excessive failed authentication, ESMTP server temporarily not available." This problem does not happen all the time but frequently.

Using Thunderbird with Xfinity email, sending an email gets the below error message. I contacted Comcast and we went through troubleshooting and could not find any problems on their end. They suggested I contact Thunderbird support. Here is the error message: "Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: resomta-po-11v.sys.comcast.net resomta-po-11v.sys.comcast.net Excessive failed authentication, ESMTP server temporarily not available." This problem does not happen all the time but frequently.

All Replies (2)

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The error tells you you have had to many send failures to connect and it is refusing to play for a period of time. It is a symptom, not the problem. What other error do you get?

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Don't get any other errors this happens a lot