FYI,

I'm getting this from Google when I try to send to the info mailbox:
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From: Mail Delivery Subsystem [mailto:[email protected]]
Sent: Tuesday, April 21, 2015 9:19 AM
Subject: Delivery Status Notification (Failure)

Delivery to the following recipient failed permanently:

[email protected]

Technical details of permanent failure:
Message rejected by Google Groups. Please visit http://mail.google.com/support/bin/answ ... wer=188131 to review our Bulk Email Senders Guidelines.
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I purchased NoesisGUI from the Unity Asset store in May of 2014, and just was trying to send an invoice number to become verified.