Okay, so my Tablet PC which is running Windows Vista Ultimate is crashing a lot lately... about once or twice every few hours. Explorer.exe crashes, then restarts eventually... After it restarts and I look at the system log, it shows at the time of the crash, an error about the Dhcp-Client. It says "The IP address lease <insert current IP> for the Network Card with network address <insert MAC ID> has been denied by the DHCP server <router IP address>. (The DHCP server sent a DHCPNACK message.)" I'm not sure why, but every time I've gotten this error like this repetitively when explorer crashes, I've had to reload the OS to get it to act normally again. I don't see why a DHCP error is crashing explorer.exe. Anyone know anything about this?