I've got a small "lab environment" with two 2019-servers and one laptop at home.
One of the servers works just as intended, and I'm allowed to RDP in to it from whatever I want to using the user account I want to. (If it matters, I've also verified that users that shouldn't be allowed to RDP can't do so.)
On the other server things don't act as I want...
I can RDP into it from non-domain computer (for instance my work computer which is member of another domain) using the administrator account, but using the account created for this purpose won't work - I'm getting a bad credentials error..
Using the same user from either the domain-joined laptop or from the other server, the user can get in just fine.
(Yes, I've tried hundreds of times from different computers, both in the network, through VPN and through WAN with port forwarding to that server. I am 100% sure the password is correct.)
Any ideas what this could be? I've also tried to add the domain\user to "allow log on through remote desktop services" in the default GPO, and I've added this user to the list of users allowed to RDP into the server (and yes, I know this
isn't usual - it's just something I've tried in order to get through the problem...)