Windows 7 Ultimate & OS X networking issues

Hi guys,

I'm having some problems with SMB style shares. First, some background.

My roommates and I are on a college campus and have always been able to access computers on the residential network via Network Neighborhood/Workgroup (aka SMB shares). This was true regardless of operating system. My server, which sits in the next room, is publicly accessible to those on the network.

For awhile, it was running Windows XP Professional SP2 and everything was fine. I then upgraded to Windows 7 Ultimate. It took me awhile to figure out how to do simple folder shares (and avoid the whole Homegroup nonsense, since non-Win7 computers can't use those). Eventually I got everything running with the same public share folders, and everything was fine.

Some time passed and we decided to upgrade the server's motherboard, processor, and RAM. Our new motherboard is an Asus M4A79XTD EVO. I planned to do a fresh install of Windows 7 Ultimate, but the operating system was clever enough to install all the appropriate drivers on its own. I installed an upgraded chipset driver set, and everything seemed fine. But then the problems began.

Initially, people transferring or streaming media from the server would be find themselves disconnected from the server, regardless of operating system. Basically, while the server could be pinged, the SMB/Samba aspect/identity of the server would disappear. The server could still see other computers (and still had internet), so from its perspective everything was fine. The only way to allow other computers to connect to shared server folders again was to reboot the server.

I tried several things to correct this, from changing the "network type" (e.g. from home to public), enabling and disabling IPv6, etc etc. Eventually, something I did (I still don't know what) enabled Windows computers (in particular, other Windows 7 machines and one Windows XP Pro laptop) to remain connected without issue. However, those using Apple computers (including me) are unable to maintain a consistent network connection with the server, requiring frequent reboots and resulting in annoyance.

My initial thought is simply a network driver issue (given the recent hardware change), but according to Windows Update we're using the latest and greatest drivers, and I haven't heard of anybody having this issue on the Asus boards and support. Subjectively, it feels like the disconnects (and subsequent connection refusals) occur when "too many" people are connected, but I have had instances where I'm the only one connected and then I'll suddenly get disconnected, so that's probably not the case. I should also point out that, following a disconnection, when attempting to reconnect, the error message that "the server cannot be connected to/reached/etc" happens immediately - that is, it doesn't actually sit there and try to connect for an extended period of time. This suggests to me that its effectively "finding" the server, but its been blacklisted for whatever reason.

Any thoughts/suggestions/hints would be greatly appreciated.

P.S. Why is simply sharing a folder such a giant pain? I don't want to deal with all this user/password/guest stuff - I want a simple folder share without any form of authentication required. And when I do share folders in Win7, randomly the "Users" folder gets shared too, which I don't want at all.

No takers?