Weird drive mapping problem

[laserblazer]

Our new server 2012/Win7 system has thrown up another strange one. Clients suddenly lose one or more shares. They may just not respond or they could be red-crossed. A moment later, they are back. Then a file won't open or opens and won't save. The drives are mapped through group policy but I'm wondering if I could create a login script to map them as well until I can get to the bottom of it. Needless to say, the staff are giving me a hard time but when I suggested they all come out so I could reboot the server, arms went up in horror. I'm waiting here for everyone to go home so I can do a reboot but I'd welcome any suggestions.

 

Edit: I've just tried opening up some machines and they are all hanging on user profile service. Could it be a profiles issue?

 

Edit2: probably not, I think the profile issues are down to not being able to see the shared drives.

Edited April 26, 2013 by laserblazer

[laserblazer]

Anyone? A reboot when everyone had gone home has got it back up and running but chances are it will fail again. I'm starting to think it could be a switch that's causing the problem but isolating that isn't going to be easy, especially as it's an intermittent fault (it happened once last week and once yesterday). Every switch in the school is less than a month old. They are unmanaged at present. Any suggestions on things I can try would be appreciated.