Cannot connect to local shares

Hi all,

We run in a strange situation with a W2k8 R2 FileServer.

We can access its shares from any computer, but we cant access its shares while logging on locally. So, if we type\\fileserver we get "Windows cannot access \\fileserver, The network path was not found". Is not working if we use the IP instead of name.

This happened suddenly. Right after we started to get errors ref GroupPolicy and when we do a gpupdate we get an error saying the server couldnt get the GPs.

I am not sure service is the one responsible for accessing network shares. I thought is Server Service but this one is responsible for shares defined locally. The thing is that the server is a production one and we cant reboot it easily.

Thanks for any suggestion,