Event Message 1004 Terminal Services Licensing When You Use the Citrix ICA Client

If the Terminal Services Licensing Service is issuing licenses to other clients, but yours can connect, and this error is logged on the terminal server, do the following:

1. Delete this registry key on the client that can't connect: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSLicensing
2. Reboot the client computer
3. Assign the local users group "Full Control" permissions to the registry key you just deleted (it's automatically recreated when you reboot)
4. Attempt to logon to the Citrix Server.