roguecoder

Ok the story is. Same time everyday any computer on the network that is currently logged into the domain Crashs. By crash i mean every currently open program (99% of them require access to the server) freezes Networked drives disappear. Some users save there application data and my documents to the server so errors about certain files no longer being available (one example is skype shuts down because of lost connection to application data) The Server itself (SBS2003 SP2) does't seem to be effected in any way. I can find nothing in the event logs that explain what is going on. Every client requires either a restart if the computer is completely locked up or if they can log out successfuly then they can log back in without any problems. I would really appreciate any help i can get. this has been a problem for the past 2 months but because it happins late in the afternoon everyone of any significance is finished and out of the office when it happins. !!!! HELP!!!! i'm begging