Assitnace with Windows Server 2012 Standard domain controller.

We have set up a windows 2012 standard server acting as a domain controller and active directory for some Dell Wyse thin clients to RDP into. Everything was working correctly but we are now getting "group policy object did not apply because it failed with error code '0x80070005 Access is denied" We also need help setting up the server to handle multiple RDP sessions. We need assistance fixing this error and with any future changes. You must be available during the day Central Standard Time US on occasion to fix immediate issues. This will be ongoing hourly work and you must have experience.