I receive logon failures connecting through the RDGW. Also, event 4625 is logged in the Security log on the RDGW. We need to turn off enforcement of channel bindings to fix this problem. Run this command and restart tsgateway service to correct the issue;
reg add "HKLM\Software\Microsoft\Windows NT\CurrentVersion\TerminalServerGateway\Config\Core" /t REG_DWORD /v EnforceChannelBinding /d 0 /f
I receive logon failures connecting through the RDGW. Also, event 4625 is logged in the Security log on the RDGW. We need to turn off enforcement of channel bindings to fix this problem. Run this command and restart tsgateway service to correct the issue; reg add "HKLM\Software\Microsoft\Windows NT\CurrentVersion\TerminalServerGateway\Config\Core" /t REG_DWORD /v EnforceChannelBinding /d 0 /f
More info at; https://support.microsoft.com/en-us/help/2903333/terminal-services-client-connection-error-0xc000035b-when-you-use-lmco