Have had Vista Business installed on my PC for nearly a year with no problems; Intel Quad-Core, 250GB HDD, 4GB RAM (matched pairs), HDD and CD/DVD are internal and SATA. HDD routinely checked by Vista and Norton DiskDoctor with no previous problems noted. Last night turned PC on and got the "BOOTMGR image is invalid" screen. Inserted the Vista CD and tried to boot from it. Got the "loading files", then the color Windows 'progress bar', then BSOD with the generic STOP ...0A error (IRQL_NOT_LESS_OR_EQUAL). Tried booting the PC into Safe Mode and get either the ntkrnlpa.exe or winload.exe "is missing or corrupt" error. I have not had a chance yet to put this HDD into my other PC and try to read the files. Lots of Qs here state the repair is to run the Vista CD Repair, so even if I can read on another PC, then??? One article said to remove all external connections, so tried that (only monitor, sound, and mouse/kybd connected), and still same errors no matter which way I try to boot. I fly out of town for the weekend this afternoon, so any help would be appreciated either this morning or in 2 days. THANKS ALL !!!!