XP activation loop, BootCamp and VMware Fusion

For at least the past month, ~5-6 times each, I'm asked to activate Windows XP Pro in both Bootcamp and VMware Fusion whenever I start it. This never used to be. I've contacted MS through the telephone activation phone number (no mean feat,) but once I got hung up on after I explained the problem and once I had to hang up myself while they were tracing my key. Compounding the problem is the fact that the activation window comes up blank where the ID should be. If I restart (either one, BootCamp or VMware Fusion) it comes up with an ID #. The automatic process never lets me activate over the Internet.
The BootCamp installation is on the internal drive and that's what I use for VMware Fusion. I have an old MacBook 1,1 (2006?) running Snow Leopard (10.6.7.) The XP Pro disc is packed in a box far away so re-installation is out of the question. Fortunately I have the key saved in OS X.
Windows informs me I have new hardware... Only, I've been running Windows this way since I got the MacBook. Did maybe a Windows, or VMware Fusion, update change things? In that case, shouldn't the activation process come up only once?
Anybody have ideas about what I can do to remove this time-consuming frustration once and for all?

 

Good instincts - I think

Thank you both. That's exactly how I've been doing it (pat, pat myself on the back) BUT I've also been using a startup launcher in Windows to not have the VMware tools loaded on startup when I know I'm going to be using BootCamp directly next. Perhaps that's now become a problem? Maybe I should always let the tools load on startup and forget about starting the Boot Camp Manager? After all, that one I can always reach from the Control Panel.
I do dread the next time I have to start up Windows directly in BootCamp, though (reserved for heavier work, and updates, it *is* faster that way.) By the way, my VMware tools version is 8.4.5, build-332101. I assume that's the latest for VMware fusion 3.1.2 as the "Update Tools" box is grayed out.