Windows 7 and vanishing SAMBA shares

If you are still getting dropped connections download wireshark to see what it going on with the network. It is the only way to troubleshoot things like this. Trying to change settings and guestimate what the problem is can take forever. I know it can be frustrating but often when you find the cause the result is that the entire network works better because you fixed a problem that was likely effecting other things as well.

http://www.wireshark.org/