Hi,
We have set up Remote Desktop Apps using Remote Desktop Services
The apps are permissioned with AD user accounts in our forest
When an external company that has network access (i.e. routable addresses) tries to log in (with credentials in our AD) they sometimes get in and other times do not. They see an error message saying 'The credentials did not work' or 'The Local Security Authority cannot be contacted'
I think this may be because all the Domain controllers for that domain are not reachable from the external company's PC
i.e. if they get lucky they try and authenticate using a reachable DC but sometimes they pick a DC that is not routable and see this error
Is my thinking correct?
How is a DC chosen by a PC belonging to an external company?
This article leads me to believe it is random: How Domain Controllers are Located Across Trusts