I have a strange issue I am hoping someone can help with. We have set-up a VPN tunnel to another organizations servers in AWS, all connectivity seems to be fine back and forth. What we cannot do is RDP to the servers in AWS, before you throw up firewall let me explain the oddities of the issue.
The consultants of the organization can come to our office and, from our network, RDP back to these machines without issue.
We thought it was a username?password issue but they tested our credentials from their machines and they were successful.
We have disabled firewalls yet still unable to connect.
We found out that from our network we can take a fresh PC, never joined to our domain and connect via RDP. Once that machine is joined to the domain the connection can no longer be made. Here is the real kicker, removing the machine from the domain, does not change the issue. Instead it still suffers the same inability to connect via RDP as the domain joined machines.
The best I can come up with is our GPO is making some registry changes that are not being reversed once dis-joined from the domain.
Does anyone have any idea of a setting that could cause this issue? I have cleared the DNS suffix, tried static and DHCP, Admin logins, Firewalls disabled, tracert looks good (issues there would be present regardless of domain memberships). I am at a loss, help would be greatly appreciated.