Hello...i have the same issue...anyone did something that worked? Please give me a reply is urgent.
Thanks in advance
Hello I know it's been a few months since this post was active but I have some insight into the issue you're having with not being able to authenticate using your OD credentials after successfully connecting using VPN from a Win 10 machine.
In my experience this usually occurs when the machine is running a non Windows 10 "Pro" version like "Home" or something similar. I've heard it's possible to directly modify some registry keys to get around this issue. I tried and didn't have much luck getting anywhere when I attempted it. That said, I've found an easier approach that works just as well. For some reason Windows 10 Home blocks the type of authentication used by OD (Open Directory) used on a mac server by default. They way to circumvent this situation is to use local directory login credentials on the server to authenticate to the share instead, like "admin". Or, you can create new "sharing only" local directory users from Server.app or from System Preferences on the Mac server that's hosting the shares and OD domain.
Just make sure that if you're doing this from the Server App to make sure you've selected the correct account type in the drop down at the top. It must say, "Local Directory" not "Local Network Directory". And then, in the section where it asks about the location of the home folder choose, "None - Services Only". That way you won't see these new accounts show up on the login screen on the server in question.
I hope this helps. It did in my situation where one of my clients had a mac mini server and a bunch of Windows 10 clients accessing the shares daily.