My friend has an HP ProBook 470, and he complained that sometimes it hangs during boot.
I've got HP ProBook 450, and after spending a bunch of time I've found out that if you will attach or detach a USB device (mouse) while Windows is starting up, his laptop will hang up. His mouse is faulty, but that doesn't matter; it just explains why hangups were rare.
The thing is my laptop doesn't have such a problem. Furthermore, I've swapped hard disks and with mine in his laptop it's not hanging up, so the BIOS (EFI legacy mode) is not the reason.
I've also enabled "Boot Logging" via msconfig, but as expected ntbtlog.txt has no records of unsuccessful startups.
To make the laptop hang you need to attach or detach a USB device (I've tried two mice) just after the blinking cursor on a dark blank screen appears and before "Starting Windows" message. If it hangs, only a hardware reset helps.
I'm not really familiar with the Windows startup process and don't know how to get logs that early on. Is that Windows boot manager that is hanging up? How do I find out the reason?
Windows activator was used on his laptop (is that blinking cursor grub4dos?).
After running bootrec /fixmbr and bootrec /fixboot I've rebooted the laptop and that "blinking cursor" disappeared along with a problem. I found that: http://media1.jex.cz/images/media1:4c5ea78d2c40c.png/w7lxe-emu1-3500.png
What I don't understand: I've tried (before fixing the MBR) as Billy_Bob suggested a friend's hard disk drive in my laptop, but it didn't hang. If the modified bootsector is located in the MBR of the friend's hard disk drive, why wasn't the problem reproduced on my laptop?