I just got a new Laptop (well my older one conked out and had no choice :()
I had just used it for 1 day and when I tried booting it today morning I was getting blue screen "Procces1_initialization_failed". So basically could not get the thing started.
So I tried seeing if startup repair could fix it. It could'nt. But the detailed error description from startup repair did throw up the info that the root cause was Bugcheck 6B...
A web search turned up a number of pages, but most were just error description. I found an post on one of the groups that mentioned that this was due to a corrupted boot cached and recommended booting from the source media and then deleting the bootcache.
In Win 7 startup repair (in advanced options) you have the option of starting a console/command window. So I just opened up a command window. The boot cache is a file called bootcat.cache and can be found in <Window>\system32\Code Integrity.
Just cd'ed into that dir and deleted the .cache file.
A reboot set everything right...