How do you limit Remote Desktop Connection access to one outside user?

zebal said:

It doesn't matter from where they are connecting, because in order for them to connect they need to do so by specifying local Administrator account username/password.

Which one of the local accounts is used for RDP?

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Unless I'm wrong on how RDP over internet or intranet works?

newly created "Accounting" account, no admin privileges, just standard user

I wouldn't know! you are probably right

zebal said:

Is there "Remote Desktop Services roles" installed on that server?
If yes, it works differently ofc; but surely remote user still needs to authenticate somehow, normaly this is by local username/pwd.

true but id still like to limit it, so not just anyone from any pc, that has the remote address can log in, just "John" from "HOME-PC"