ok how the h___l did this happen

i was working on my wince .net project trying to up date it throw ifr when i gave up after 2 hours of trying i shut down my laptop this morning wake up going to try again and i got a hdd master password #L13T36196VE-5958 its asking me for i never set one first it was admin password got that fixed now this whats up. HOW DID THIS HAPPEN AND HOW DO I FIX IT