Lookup for "552 2.5.0"
This status code indicates a successful delivery or other operation. Any details are simply notes.
Basic Status Code Details (552)
Requested mail action aborted: exceeded storage allocation
Enhanced Status Code Details (2.5.0)
Other or undefined protocol status
Something was wrong with the protocol necessary to deliver the message to the next hop and the problem cannot be well expressed with any of the other provided detail codes.