Having Vista's SP1 to install without a hitch is simply luck of the draw unfortunately. The latest version of SP1, at least to my understanding, actually installs a prerequisite update and it's that update that appears to be screwing up people's comps.
People have reported success starting from scratch and installing SP1 onto a fresh install of Vista (before adding any other apps).
edit: I did some more reading and supposedly M$ pulled that prerequisite update, so that blows my "theory" out of the water. I assume you already tried Safe Mode?
Seems like M$ updates do more to damage systems than to help them. I had a failed Vista update yesterday and the system would not boot at all. Had to do a restore with Acronis last night.
Last edited by bistro; July 3rd, 2008 at 09:21 AM.
Desktop: Intel i7 960 CPU @ 4.0GHz, EVGA Classified 4-Way SLI mobo, 12GB Corsair Dominator-GT 2000 DDR3 RAM, Crucial RealSSD C300 256GB Solid State Drive, Two WD 2TB SATA drives, 2x EVGA GTX 570 Superclocked graphics cards in SLI, Coolermaster HAF X full tower case, OCZ ZX 1250w PSU, Corsair H100 CPU Cooler
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