[Rumpus-talk] Drop Ship = Error sending mail. Server returned SMTP code 553

[Michael Scott]

When any user has his email address filled in (in the User Info section), and when that user tries to send a file via Drop Ship they get this error (shows up on a rumpus page) -

Error sending mail. Server returned SMTP code 553 ("Requested action not taken: mailbox name not allowed.") while sending MAIL FROM command.

Then from my regular email (I use AT&T) I get this email -

Important: Verification Required - Action Needed
Dear AT&T Internet Services Member,
We have received questions regarding the following error message which is received by customers when they send e-mail using a non-verified e-mail address:“Unable to send the message. Please verify the e-mail address in your account properties. The server responded: 553 From: address not verified.”
I understand what is happening - my mail server gets an email request via SMTP but it can't verify the address. BTW, I do receive email notices for uploads etc., just fine, but drop ships (w/ user email field populated) won't go through. My fix is to remove their email address from their account info settings and then it works (but obviously the recipient can't see who it's from). Of course my email is there, but not theirs because I removed it.
Not sure what to do. I can't add every single email account of every user in my AT&T email account, there's just too many, and even when I tried to add just one (in my AT&T verify/add account/email) it still didn't work and the error code 553 popped up.
Michael
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