Windows 2008 R2 Terminal Server Error: The task you are trying to do can't be completed because the Remote Desktop Services is currently busy. Please try again in a few minutes. Other users should still be able to log on. Solution/Fix/Remedy

The following is not a permanent solution or fix, but the steps should help logging users back on the terminal server without having to reboot and inconvenience other users logged on.

1. Log onto the terminal server and open the Remote Desktop Services Manager.
   
2. Select the terminal server you are logged onto in the left hand pane. (if you are logged on remotely you may not have sufficient permissions to end processes).
   
3. Get the Session ID of the hung session(s)

1. Click on the Sessions tab. Look for sessions which display the following characteristics (as the image above):
    - Session: Disconnected
    - User: [BLANK]
    - State: Disconnected
    - ClientName: [BLANK]
    - LogOnTime: Unknown
   
2. Take note of the ID field. In the screen shot above this is "6".
   
3. NOT REQUIRED: This step is not required but can be useful: If you right click on the session, click "Connect", enter a domain administrators password and click ok, you can connect to the session and can see at what stage the login has hung.
   
4. Free the hung session(s)

1. Click on the Processes tab, click on the ID column to sort the processes by ID. Scroll down through the list and find processes matching the ID gathered from the previous step (in this example "6")
   
2. Commonly with this particular error, only 3 processes will be visible - LogonUI.exe, winlogon.exe, and csrss.exe
   
3. Right click on winlogon.exe and click End Process. Once you end this process the other 2 should disappear. WARNING: do not end csrss.exe, this will crash and reboot your terminal server.
   
5. Now get the user who was having difficulties logging on to try again.

Cheers