Because of an error in data encryption, this session will end. Please try connecting to the remote computer again

Cause:
Microsoft says  this is a potential race condition between the Icaapi.dll and Rdpwsx.dll dynamic-link libraries (DLLs) may cause the private certificate key on the Terminal Services server not to be synchronized.

Resolution:
Important: This procedure involve modifying the registry of the server, please take extra caution by backing up your registry key before proceeding

To resolve this issue, follow these steps:

1.    Start Registry Editor.
2. Locate and then click the following registry subkey:
         HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\TermService\Parameters
3. Under this registry subkey, delete the following value (s):
             * Certificate
             * X509 Certificate
             * X509 Certificate ID
4. Quit Registry Editor, and then restart the server.

I hope this helps!