Repair Windows using an upgrade disk?

[McKay]

Last night I installed some new RAM in my system, Windows decided to die. Because HP were kind enough to not include a recovery disk, and I was too stupid to make my own, can I buy an upgrade disk, boot into that and run the repair facility? It passes UEFI fine, all the hardware passes the hardware check, however Windows fails to boot so I believe its become corrupted. I've seen something similar at work where swapping out the video card corrupted the Windows install.

Quick answers would be really appreciated, I'm writing this on my phone from Tesco carpark. Need to know before I walk in and buy one, I've googled and can't get a straight answer.

[BeerFan]

What OS is it? Have you tried booting into Safe Mode?

Yes, if you buy an upgrade disk, you should be able to run the Repair function.

[Hum]

There should be a recovery partition on the HP hard drive.

Look for it and run Recovery from the boot-up screen.

Try the F8 key on boot, if you don't see a choice then.

[LittleNeutrino Veteran]

i would try the recovery partition, generally no one is handing out recovery software for windows 8, i am not certain if you can download a recovery disk from Microsoft for Windows 8 or not, i know that you could for windows 7.