SMTP Error Code: 251 5.7.7

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Lookup for "251 5.7.7"

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 (251)

User not local; will forward to

Enhanced Status Code Details (5.7.7)

Message integrity failure

A transport system otherwise authorized to validate a message was unable to do so because the message was corrupted or altered. This may be useful as a permanent, transient persistent, or successful delivery code.