Intermittent network login issue

Hi folks,
I have a Server2008 Server running as a Terminal Server and ever now and then when someone tries to log in, they get their username and password request OK but when they hit enter they get a message saying "Invalid Network Address".

If they input the IP address instead of the server name in the RDP box they can connect, but if they log out and try the server name again, they get the same message.

Wait 10 minutes and the problem goes away.

I figure it must be DNS related somewhere but can't see anything that looks out of place.

Any suggestions?

 

The server is issuing IP addresses, is acting as the DHCP server? How large of a range of IP's are there and how many users are logging in? What is the amount of time for a disconnected session to release the IP? Does this happen once most everyone is logged in and you would expect the licenses to be close to all being taken?

It sounds like disconnected sessions are not releasing very quickly and you are close to your max available IP's and/or licenses or you just have a lot of users who log in and out.

I use static IP's and haven't tinkered with the server 2008 much yet so I don't want to lead you in the wrong direction. I do use some DHCP recently and if this were happening to me, I would give the user with the most trouble a static ip outside of the range of the DHCP setting and see if that eliminates their problem. Then I would go into the local user settings and tinker with the session / disconnected / idle session settings to find what works more efficiently for your situation.