Windows 10 Logins and shared resources not functioning

Question

(Actual IPs and Server names have been removed and replaced with examples)

Point 1: We can not login to the domain unless we remote connect to the server and login, There are no login servers available.

Point 2: I can not access shared resources on \\SERVERNAME\, but if I connect over the VPN we have setup (\\10.0.0.2\). We get the error

\\SERVERNAME\ is not accessible. You might not have permissions to use this network resource. Contact the administrator of is server to find out if you have access permissions.
Multiple connections to a server or shared resource by the same user, using more than one user name, are not allowed. Disconnect all previous connections to the server or shared resource and try again.

So what do I do, kinda stuck in a weird position of everyone not being able to sync their files, and not being able to use work accounts on their PCs.

Any ideas?

Answer 1

Sorted the issue, I just realised I added it as a network controller.

(If you have a similar issue):

Try demoting it from a network controller, use another machine if you really need one.

1- Open the server manager

2- Head to Tools > Remove Roles and Features > Next > Role Based > Pick the affected server > Remove Network Controller and RSAT

3- Hit remove

4- Restart the machine