Attempt to connect using the administrative console mode by running mstsc /v:[ServerName] /admin in the Run dialog.

A specific Group Policy setting regarding removable devices has been known to interfere with RDP sessions. Press Win + R , type gpedit.msc , and hit Enter.

Navigate to: Computer Configuration > Administrative Templates > System > Device Installation > Device Installation Restrictions .

In some enterprise environments, mismatched security layers (SSL/TLS vs. RDP Security Layer) can trigger this error.

Use the Microsoft Learn Guide to verify that the RDP listener is active on port 3389. 4. Adjust Security Layer and Admin Switches

If you are connecting via a hostname, try using the IP address instead to rule out DNS resolution issues.