You must install it in this order:
Install KB958559 (VirtualPC) first , next the Update KB977206 to remove the VT requirement (if your CPU doesn't support hardware VT) and in the 3rd step install the XPMode VHD (WindowsXPMode_en-us.exe).
Download the XPMode VHD from here:
"A programmer is just a tool which converts caffeine into code" CLIP- Stellvertreter http://www.winvistaside.de/