Lookup for "250 2.1.4"
This status code indicates a successful delivery or other operation. Any details are simply notes.
Basic Status Code Details (250)
Requested mail action okay, completed
Enhanced Status Code Details (2.1.4)
Destination mailbox address ambiguous
The mailbox address as specified matches one or more recipients on the destination system. This may result if a heuristic address mapping algorithm is used to map the specified address to a local mailbox name.