When accessing a server locally using its own FQDN or CNAME alias, Windows may block the loopback authentication request. Adding the hostname to BackConnectionHostNames resolves this.
Reference: Accessing a server locally with its FQDN or CNAME alias denied
regeditHKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\MSV1_0
BackConnectionHostNamesNote: Add one hostname per line in the multi-string value — e.g.,
myserver.domain.local