SMTP Error Code: 221 5.2.1

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Lookup for "221 5.2.1"

Permanent Error - This status code indicates a permanent issue and is unlikely to resolve itself. You should contact the Email Service Provider.

Basic Status Code Details (221)

Service closing transmission channel

Enhanced Status Code Details (5.2.1)

Mailbox disabled, not accepting messages

The mailbox exists, but is not accepting messages. This may be a permanent error if the mailbox will never be re-enabled or a transient error if the mailbox is only temporarily disabled.