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Email Stops when Enabling Comprehensive Anti-Spam Service
03/26/2020 18 12516
When enabling Comprehensive Anti-Spam Service (CASS) on the firewall inbound email flows stop. When troubleshooting there is an SMTP error: "503. 5.7.1 client failed to authenticate (utm 43)" .
The SMTP error ?????503. 5.7.1 client failed to authenticate (utm 43)??? is license related. Confirm that the SonicWall firewall is "Trusted" on mysonicwall.com.
When on mysonicwall.com click My Products and click the firewall. Locate the Trusted status. If the status is "No" this confirms the CASS issue is due to licensing.
The license on the firewall must be reset and then synced to mysonicwall.com. Please refer to Resetting the Trust. In most situations the firewall does not need to be rebooted.