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SMTP Server??

Posted by
Frequent Visitor

Message 1 of 7

Not sure I'm posting in the right place, but since last night I can't send emails.  I'm using Thunderbird, and have not changed any settings anywhere.  The only time I've ever had a problem w/this is when it was at Comcast's end.  Is there a problem today with the SMTP server?  This is the message I get:



Sending of message failed.
The message could not be sent because connecting to SMTP server smtp.comcast.net failed. The server may be unavailable or is refusing SMTP connections. Please verify that your SMTP server settings are correct and try again, or contact the server administrator.




Help is appreciated.


Accepted Solutions
Posted by
Silver Problem Solver

Message 4 of 7
Posted by
Silver Problem Solver

Message 2 of 7


Please be aware that comcast has changed there port setting. Have you made the changes?

Posted by
Frequent Visitor

Message 3 of 7

No, I had no idea.  Is this very recent?  It was working yesterday.  Did they make customers aware of this? 


Ugh, would you happen to know what the settings are supposed to be?


Thank you, reasd.

Posted by
Silver Problem Solver

Message 4 of 7
Posted by
Frequent Visitor

Message 5 of 7

Yes!!  Thanks so much!  Not sure why I didn't receive the notification of the changes, but just happy I can now send again.


Thank you. Smiley Happy

Posted by
Gold Problem Solver

Message 6 of 7

The change is still being rolled out in some areas.  You should have received the email about it in your Primary Username Inbox in XfinityConnect.


Basically, here is the contents of that email for your reference.



Dear Valued XFINITY® Internet Customer,
We care about your email security when using our network. On August 1, Comcast announced that for security reasons we will no longer support the use of port 25 for sending email from programs like Outlook or Apple Mail. It appears that one or more computers connected to your Internet account are using port 25 to send email. A port is a connection through which information flows from a program on your computer, from another computer in a network, or to your computer from the Internet, Port 25 is an unsecured port, and it is increasingly used to send spam emails through malicious computer programs called malware. These spam emails are usually sent by computers that have been infected by viruses, and as a result, most users are unaware that their computers are sending spam. By no longer supporting port 25 to send e-mail, this will help prevent your computer from sending spam without your knowledge.
What You Need To Do:
We are asking you and other impacted customers to change your email program settings to port 465, which provides more security. You will be unable to send email over port 25 once it is disabled, and you will need to update your settings to port 465 in order to continue to send email.Please click the link below for your current email software and follow the step-by-step instructions to change your settings.

Need Email Help? Please post the following information in your post.
Do you use XfinityConnect? The Full or Lite version?
Do you use an email client? Which one? (Eg; Windows Live mail, Outlook, a smartphone etc.)
Which browser/version do you use? And- have you cleared your browser cache?
Which operating system? XP, Vista, Windows 7, Mac OS X
Details of the problem you are having.

Posted by
Gold Problem Solver

Message 7 of 7