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Outlook with Comcast email sending report error (0x800CCC78)

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Outlook with Comcast email sending report error (0x800CCC78)

Outlook 2010 with Comcast email sending report error (0x800CCC78) : Cannot send the message. Verify the email address in your account properties. The server responded: 550 5.1.0 Message sending error for (my email address).


Sending from Comcast website no problem but can't send on cell phone or Outlook 2010.

This coincided with an email from: do-not-reply@comcast.net with only the subject line: Comcast Email Sending Limit Exceeded.


There is no 'From' where my name used to be on the outgoing box area. It's like Comcast has blocked me somehow. I tried resetting the computer and the Wi-Fi machine and nothing worked. I've checked various posted online help suggestions and nothing seems to be working. Comcast won't help because technically it's an OUTLOOK problem since I could send something from their website.


Thanks for any help!