I kept having issues with business customers Windows 10 systems.
They could not RDP to their servers and network resources from home, or across town.
This is a known Windows 10 to Server 2012 issue. Below is the Fix I used to get my customer working.
1. On the Windows 10 system launch regedit.
2. Browse to HKEY_CURRENT_USER
5. Terminal Server Client
6. Right click on Terminal Server Client and go New DWORD (32-bit)Value
7. Name It: RDGClientTransport
9. Base: Hexadecimal NOT Decimal