Here is the full explanation of the tool ( licdiag.exe / licensing diagnoser ), including how to run it, interpret its full report, and common issues it detects.
Alternatively, you can install it via using the following command from sources like Carl Stalhood : Install-WindowsFeature rsat-rds-licensing-diagnosis-ui How to Access and Use It Once installed, you can open the tool by: remote desktop licensing diagnoser
While the error messages users receive can be vague, the underlying cause is usually structural. The Remote Desktop Licensing Diagnoser removes the guesswork, pinpointing exactly why the handshake between the Session Host and the License server is failing. For any administrator setting up a new RDS farm or troubleshooting sudden connection drops, running this tool should always be the first step. Here is the full explanation of the tool ( licdiag