SMTP Error Code: 221 2.1.7

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Lookup for "221 2.1.7"

This status code indicates a successful delivery or other operation. Any details are simply notes.

Basic Status Code Details (221)

Service closing transmission channel

Enhanced Status Code Details (2.1.7)

Bad sender's mailbox address syntax

The sender's address was syntactically invalid. This can apply to any field in the address.