johnbo

Hi everyone, im new to this forum but I need help so desperately. If anyone can point me in the right direction I would be eternally grateful.
I have 5 vista 64 computers connected through a switch, I use them to render 3d scenes across a network using maya, I have setup a shared folder on my main pc that holds the project files and also the renders, all of them are setup to render frames to \\JOHN-PC\3dwork\renders and at first this works fine, but after between 1 and 5 hours something will happen, I start getting an array of errors popping up.
Logging into a remote computer will confirm that the shared drive on my main PC is no longer accessible, giving an array of \\JOHN-PC is not accessible errors.
These range from access is denied, server does not have enough storage, server cannot perform specified operation, and such depending on my networking settings but the result is always the same, some time of rendering with no problem then a fatal error which needs all machines to be fully restarted to solve. This is obviously a real problem for me as I want to render a lot overnight while I am not actually working on a project but I cant let the computers out of my sight for a moment as they will fail.
I have tried a slew of fixes from various internet sites from tweaking uac and permissions to adding registry entries but nothing seems to work, some settings delay the failure but it never fully goes away, if anyone can shed some light on this problem I would be extemelely appreciative as I am losing lots of sleep and getting behind in my work. PLEASSSEE HELP ME, PLEASE, PLEASE.