SMTP Error Code: 221 4.3.0

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Lookup for "221 4.3.0"

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 (4.3.0)

Other or undefined mail system status

The destination system exists and normally accepts mail, but something about the system has caused the generation of this DSN.