Hi dear,
Please provide the details about the following component.
Can you tell me this error occurred while you publishing RemoteApp or publishing the full Remote Desktop?
Have you changed some settings before getting started with the Remote Desktop connection?
Does the connection depend on two devices or an RDS environment deployment (this contains the servers and roles to create a fully effective RDS environment)?
Also, please descript the environment configurations based on Remote Desktop Services deployment.
If the errors occurred in an RDS environment, do errors happen on most users or some user?
In the meanwhile, you could check the System event logs via Event Viewer and see if there are Schannel error occurred.
If the answer is helpful, please click "Accept Answer" and upvote it.
Best regards