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Troubleshooting
Fix issues with common problems
- 421 4.5.1 Too many errors, you have been temporarily blacklisted
- Diagnosing SMTP Connection Issues to SocketLabs
- Diagnosing and Reporting a Service Outage
- 552 5.1.7 - The sender's address was syntactically invalid
- Message Delivery Failure Codes
- Recipient List Format
- Error When Downloading Report Data
SocketLabs Inbound SMTP Gateway Errors
- 421 4.4.5 - Too many connections from your host
- 552 5.3.4 - Message too big for system
- 554 5.1.0 The Sender's Address Was Not Allowed
- 501 5.7.0 - Authentication failed. User name or password is invalid.
- 452 5.5.3 - Too many recipients
- 550 5.1.3 - The destination address was syntactically invalid
- 451 4.7.1 - Your account has been temporarily suspended
- 501 5.7.0 - Authentication required. Please authenticate with CRAM MD5 or AUTH Login
- SocketLabs Inbound SMTP Gateway Errors