The DNS server encountered a CNAME (alias) resource record (RR) in zone file %1 at line %2 for a domain name with existing ...

The DNS server encountered a CNAME (alias) resource record (RR) in zone file %1 at line %2 for a domain name with existing RRs.  Where used, CNAME RRs must be the only RR for the domain name they are used to provide an alias for.  Either this CNAME RR, or the one it conflicts with, needs to be deleted from zone file %1, which can be found in the %SystemRoot%\System32\Dns directory.