This solution applies to all Barracuda Spam & Virus Firewalls, Version 5.x and up.
To verify the domain you wish to utilize the Cloud Protection Layer (CPL) with, the MX record for the domain has to resolve and point to the physical Barracuda Spam & Virus Firewall. This is to verify that the Spam & Virus Firewall associated with the Barracuda Control Center account is the one we are configuring the CPL to utilize. If the MX record is currently not pointing to the Barracuda appliance, you will need to change the MX record temporarily to allow the domain to be verified. Once verified the CPL setup can continue normally.
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