Remote Desktop/Terminal Services - Error In The Licensing Protocol

One of the most common errors that I see working with RDS/TS is when a user attempts to connect and they receive the following message:

"The remote computer disconnected the session because of an error in licensing protocol."

Thoroughly frustrating but happens so often when licences either run out. 

Microsoft's solution is to remove the MSLicensing registry key which will resolve the issue if it's just an expired licence.  The problem still happens though in Windows 7 even after you remove that key and it's all down to that effective but stupidly annoying User Account Control (UAC to those in the know).




You can turn this off and I personally do on servers running 2008 R2 due the horrible things that go wrong with applications but workstations used by your users it can be very helpful in stopping them from doing stupid things.  In my personal opinion, you should lock them down enough that UAC is unnecessary but I am aware this isn't always possible.

So first of all, you'll need to do as Microsoft says and remove the registry key from the registry hive. 

1 - In Windows 7 with UAC on you will need to run Regedit as an Administrator.  To do this search for it on the start menu then right click and select "Run as administrator".

2 - Click Yes to run the registry editor.  Note that you will need to provide Administrative credentials if you are not logged on as an adminstrator (grandmother and some eggs anyone?).  Now you're in there follow this track:

HKEY_LOCAL_MACHINE --> SOFTWARE --> MICROSOFT --> MSLICENSING

3 - Click MSLicensing and then press Delete or right click and select "Delete".  Click OK to confirm.  Close Registry Editor.

4 - Now the key has been deleted you need to run Remote Desktop Connection as an Administrator.  This is the part that the Microsoft article leaves out for Windows 7.  To do so search for it in the Start Menu and then right click it and "Run as administrator"

5 - Now attempt to connect to the Remote Desktop/Terminal Services server and you should find it works again.


Final notes...

Licensing is getting more complex now and fooling a Terminal Server was easy but Remote Desktop Services has had an upgrade to stop you from cheating the system.  Ensure you have enough licenses and remember they are not concurrent.  Once issued you can only redeem them by trashing the licence server and starting again.  Painful but that's how Microsoft make their money...