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Error 5.1.1 Not our Customer... Mail could not be sent... Error: -17099

New Poster

Error 5.1.1 Not our Customer... Mail could not be sent... Error: -17099

Are you going crazy over this one? So was I... so I wrote this explanation in way that I hope will make sense to any of you poor people who are trying to find an answer elsewhere lol - I've been there!!! Please let me know if it helps!

 

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When attempting to send email to a single person or to a group, the following message appears: 

Error

5.1.1 Not our Customer

 

Explanation

Mail could not be sent.

Account name: "[account name]"

 

Error: -17099

This error is occuring because you are sending mail to a person with a comcast email address, and that email address is invalid. If you are sending an email to a group, take out the comcast email addresses and try it again. It works, right?

 

Now you can try one or two comcast email addresses at a time and narrow it down to which one(s) is causing the problem.

 

 

Frequent Visitor

Re: Error 5.1.1 Not our Customer... Mail could not be sent... Error: -17099

This fix doesn't really help me though, as the comcast email address that keeps getting rejected is MINE!

It thinks I'm not a customer!!!!

 

It doesn't matter who I send emails to since comcast's servers think I'm not their customer, they won't send ANY of my emails.

New Poster

Re: Error 5.1.1 Not our Customer... Mail could not be sent... Error: -17099

Wow, you even tried sending one e-mail to a non-comcast customer?
Service Expert

Re: Error 5.1.1 Not our Customer... Mail could not be sent... Error: -17099

skc, in order to avoid the confusion that arises when one has the same issue in more than one thread, please keep all discussion of your problem in your thread HERE.

It's easier for you and those who are helping you if it's all in one place.




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Re: Error 5.1.1 Not our Customer... Mail could not be sent... Error: -17099

New Poster

Re: Error 5.1.1 Not our Customer... Mail could not be sent... Error: -17099

After 2 hours on echat with a Comcast rep--I figured this out by myself.  THEN found this website with the answer.  Why didn't tha rep tell me this???  I gave her the Error #!  And yes--this worked.  One stupid email with an invalid comcast email held up my entire eBlast and took 2 hours to figure out.  TRAIN YOUR REPS BETTER!!!