I've encountered similar issue. I have two PCs, one with Win7 RC b7100, second with WinXP SP3. PC1 has two LAN interfaces, one (lan1) connected to provider LAN, second (lan2) connected to PC2 via crossover. lan1 is 10.x.x.x/8 range, has default gateway and DNS set. lan2 is 192.168.0.1/24, no GW...