If you are getting a Reset Node Error when you are opening your WSUS console on Windows Server 2012 R2, first attempt to restart all associated Windows services (Update Services, WID / SQL, etc.). If that has not fixed it, open a command prompt with elevated privileges and run the following commands:
cd C:\Program Files\Update Services\Tools
Wsusutil.exe postinstall /servicing
If you do not have he wsusutil.exe in that folder, simply search for it on the C drive as the WSUS original installation would have placed it in a temporary folder as well as the intended folder.
You can now start the WSUS console successfully.
If you have any questions or issues feel free to contact me on alex@L3consulting.com.au.
Alex Tarata / L3 Consulting