SMTP Error Code: 221 4.2.0

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Lookup for "221 4.2.0"

Temporary Error - This status code indicates a transient issue and may resolve itself.

Basic Status Code Details (221)

Service closing transmission channel

Enhanced Status Code Details (4.2.0)

Other or undefined mailbox status

The mailbox exists, but something about the destination mailbox has caused the sending of this DSN.