For quite a while I've had a reasonable well-working system that works for running Windows XP sp2 in both Boot Camp and Parallels (using the same installation of XP). Suddenly I can boot XP in Parallels, but not Boot Camp. In Boot Camp, it just goes to a black screen, no cursor, no splash screen etc. I've been unable to even get to "F8" help screen. I do see this article: http://kb.parallels.com/en/4672 however I'm not sure if this is the same issue and I'm hesistant to proceed.
Ok, Perform Windows installation repair in Boot Camp, and Clear Parallels Desktop information from Boot Camp Configuration Editor-Hard Disk 1 Advanced -Clear Not you need to activate Windows again