Beginning with the release of Windows Remote Client (RC) 1.11.0, EDNS was added to local domain queries for failover.
After upgrading to RC 1.11.0, if local DNS resolution is failing the likely cause is that either EDNS isn't supported, such as with Windows 2012/R2 (no longer supported by Microsoft), or that a firewall is blocking EDNS queries.
Add a registry entry to disable EDNS for local domain queries for failover.
reg add “HKLM\Software\DNSFilter\Agent” /v IncludeLocalResolversEdnsRecords /d “false” /f
reg add “HKLM\Software\DNSAgent\Agent” /v IncludeLocalResolversEdnsRecords /d “false” /f
To reenable EDNS for local domain queries for failover, set the registry value to true.