U

Tuesday, March 4th, 2025 11:51 PM

Excessive failed authentication, ESMTP server temporarily not available

I am having issues with my comcast outgoing email over SMTP from my home wifi network. When I atttempt a telnet test I am getting the "421 resomta-a2p-647652.sys.comcast.net resomta-a2p-647652.sys.comcast.net Excessive failed authentication, ESMTP server temporarily not available" error message. It appears as though my IP may be blocked for some reason. I've just noticed this in the last week or so but I don't use Comcast to send as often as I receive. Please advise.

Gold Problem Solver

 • 

26.3K Messages

10 days ago

... Excessive failed authentication ...

This is usually due to a device, program, or app connecting to Comcast/Xfinity's mail servers with incorrect user/password information. Following the procedure described in https://forums.xfinity.com/conversations/email/possible-solution-for-unable-to-connect-to-email-from-apple-maybe-other-devices-after-changing-comcast-password/65a1a8fbf961c6163a367c6f may clear the problem.

Please be aware that there are 2 kinds of responses in this Forum: Replies and Comments. When you Comment on a post by scrolling down to "Comment on this post here...", I am notified of your response. But if you select Reply, I am NOT notified and may not be aware of your response.

Official Employee

 • 

1.2K Messages

8 days ago

 

user_2mz8x7 Can you please send us a DM. You can start by clicking the chat icon located in the top right corner of your forums' page when signed in. Once there, you can direct your messages to "Xfinity Support." Please add your full name and service address to help us locate your account. Let me know if you have any questions. 

 

forum icon

New to the Community?

Start Here