Windows 10 Remote Desktop Session Randomly Unexpectedly Terminates
Solution 1:
I believe this issue has been fixed in Windows 10 build 19018 (20H1), which is available to Windows Insiders. You should be able to get this if you're willing to switch to the Slow ring in your Windows Insider Settings.
I've been experiencing it as well and it seems to have gone away after upgrading.
Solution 2:
This link shows that it is possibly group policy updates although the solution provided does not always work.
Although this might work for you:
The best workaround I found is to increase the interval between group policy refreshes. I set it to 8 hours (480 minutes) for domain controllers and now I get at most one RDP reset a day.
Quoted from this page.
EDIT:
It could possibly be this:
Or Most probably you have switched on "Dynamic lock". This detects if you are using the computer or not and locks it if you seem to be away.
You can find this at: Settings (Windws+i) -> Accounts -> Sign-in options -> Dynamic lock
Qouted from this page.
Try doing Win+R and mstsc.exe /admin
and staying logged on like this. Then see if it shows a "Logging off..." message when the error happens.
Solution 3:
I faced the same issue. The solution eluded me until I noticed the clock was off. I update the time server and still had problems until I restarted the server.