I got an HP8540W laptop a couple of months ago and at the time I had a bit of fun and games installing it. The machine has a main drive in it (SSD) and a secondary bay that can take a DVD-drive or another hard-drive and I have another hard-drive in there.

I’m a bit “manual” when it comes to installing operating systems and so when it came around to doing this I thought that there’d be no problem in that I’d just put the OS onto a USB key, boot from that and then install.

this walk-through takes you through using a USB key to install Windows 7

Suffice to say that, at the time, I got so fed up with trying to make this work that I ended up taking out my 2nd hard-drive, dropping in a DVD drive (having made a DVD ) and installing from that DVD.

Why? Because I would find that I had no problem whatsoever getting the laptop to boot from the USB key but then whenever I got to the stage of being about to install the OS I would get the dreaded;

“Required CD/DVD drive device driver is missing”.

This is always a bit puzzling and especially when you’re in a situation where you don’t have any kind of CD/DVD drive at all and you’re wondering what Windows might be looking for.

In my case, I suspected that I knew what Windows was looking for – despite the laptop having booted from the USB key the installation process is looking for a driver that lets it talk to the USB key and I’m not sure whether this is because the laptop has USB 3 ports or not.

At the time, I downloaded the driver from HP (it seems to be an NEC USB 3 and that link is to the 64-bit download) and I know that I couldn’t get it to work but, having revisited it, I’m not 100% sure whether that was because;

1. I couldn’t get the OS install process to then accept that driver off a USB key or maybe an SD card ( I know I tried both ).
2. I didn’t quite follow the right steps.

I’ve just been around the installation loop again on this machine except this time I was installing a new Windows 7 into a bootable VHD file.

 Hanselman has a good article on this here.

I hit the exact same problem except this time around I know that when I reach the “give me a CD/DVD driver” stage I already have filesystems available from the existing OS and so I can put the driver on one of my existing partitions to feed to the installation process and so I;

1. Downloaded the NEC 3.0 USB drivers.
2. Stuck them on my C: drive.
3. Made a bootable USB key.
4. Made a blank VHD to install the OS into.
5. Rebooted and booted off the USB key.
6. Attached the VHD file so that I could install into it (via SHIFT+F10 and diskpart – see Hanselman).
7. Got to the point where my laptop said “Required CD/DVD device driver is missing”
8. Fed it the NEC 3 USB driver off my C: drive which HP unpacks to some Files\x64 folder.
1. Important point – I had to untick the “hide incompatible drivers” option which then reveals 3 drivers that I installed.
2. Important point – I had to unplug and replug the USB key at that point.
9. Installed into the VHD file.
10. All is good. I think.

So if that helps anyone out there installing to an HP8540W or maybe installing Windows 7 generally with USB 3 ports then that’s great and apologies that it’s not a 100% guaranteed set of instructions because I’d have to flatten my laptop to be 100% sure of what the process might be when starting again from scratch.

If anyone spots the specifics of what’s going on here and wants to add better guidance via comments then feel (as always) very free