Where I work, access to the network by hardware is (somewhat) controlled by using hardware MAC addresses to identify machines before DHCP will issue IPs etc. Parallels emulates RealTek Ethernet adaptors, which have their own MAC addresses. Because I use Bridged Mode rather than Shared networking, I had to get that MAC address registered with our network admins, too. Once that was done, Windows XP worked like a charm. However, later I also created an Ubuntu VM setup that worked at home but not at work, and today when I got time to look at why, it dawned on me that Parallels allows you to run multiple VMs at the same time. Therefore, each VM is assigned its own MAC address. Copying the MAC address from my WinXP configuration to the Ubuntu configuration solved the problem -- the network became available once I also set the networking to use en0: Ethernet Adaptor (as the "default" did not seem to work). Anyway, this is just a reminder for those in similar situ...

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