I've got similar issue as some of the other users here with Virtual PC 2007 SP1. My host is Window XP SP3 (with the latest updates and One Care) and guest OS is exactly the same as the host. Problem is:
1. When I start the VPC, using my physical network adaptor, I get an IP address conflict on the guest only, however I'm able to browse the internet from within the guest. I do however get the constant error "IP Address Conflict ....".
2. When I change the settings on the VHD to use MS Loopback adaptor (which I've installed as per instructions on this thread) I don't get the IP conflict anymore. However I'm NOT able to browse the internet from within my guest.
It's like I can have one or the other not both! I've give the loop back adaptor a static IP and have also given a different IP within the Virtual OS (cannot give it the same as this will bring back IP address conflict). The gateway addresses are the same in all the "three" adaptors. The physical adaptor is getting the IP dynamically from my router and I have NOT reserved the IP in my router for this adaptor.
Given the above what else can I try to make Point 2 above successful? Any help would be appreciated, and can provide any info. Before anyone suggests, I would like to use Virtual PC only not virtual server and I need this server for certain projects where I do not want third party installs on my host system, thus keeping it clean.
Thanks in advance!