Opening your mail account settings and UNCHECKing the option to "This server requires a secure connection" for both Outgoing mail (SMTP) and Incoming mail (POP3)."
Likewise, this error can occur when too many recipients are in the "To" line.. Tried reducing those?
It would sure help if we knew which email client you're using though.. And this error can also happen if you don't have a comcast account.. Do you have one? (Just making sure..)
Hope this helps.
Grif
Am running OEM Vista Home Premium. TThe problem I am having is sending mail. I can recieve fine but get the following error messeage.
.
Account: 'mail.comcast.net', Server: 'smtp.comcast.net', Protocol: SMTP, Server Response: '550 [PERMFAIL] comcast.net requires valid sender domain', Port: 25, Secure(SSL): Yes, Server Error: 550, Error Number: 0x800CCC79
It seems comcast is blaming Microsoft and Microsoft blaming Comcast.
Now I am in the middle with a sprogram that does'nt work.
Any help would be aopreciated.

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