Hi
@RyanClearI had this issue previously and it was because the temporary set up we were using was creating too many remote connections to the machines and it was usually things like Activate, focus etc that this error appeared. Can i ask how your resource machines are set up? are these virtual machines or physical? are they always on and you are using unlock screen instead of login? If you are using the unlock screen instead in login then you may be creating persistent connections to the machine and you are seeing this error because the process cant identify which connection is attempting to do the action.
There is one way to see how many connections there are to the machine, open a command line and type the following
qwinsta /server:{IP address of the resource machine} if you see RDP-TCP connections with multiple connections then this could be the issue. If there are multiple remote connections then if you change to use logout and login then this should clear all connections.