BIOS access is fine. It's access to the BIOS boot menu to select boot from USB etc.

oh right, I don't think I've ever known that to be a problem once you're in

Probably not explained myself correctly. When you boot there's often a message on the POST screen to press something like F8/F10/F12 which brings up a screen with a list of bootable devices. It's this message and option which seems to be missing.

I've recently stopped using MSSE and started using Bit Defender (Free). Supposed to be one of the best you can get and it's very light.

Go into BIOS and change boot order.

I'll give that a go. Currently doing a startup scan with Avast. I feel like I'm going to kill the computer removing all these infected files that can't be repaired.

Tried that, didn't seem to work for some reason, the USB drive wasn't an option. I tried with "bootable addon cards" first.

Think that was for Kosser.

Probably was. My quick reply box doesn't seem to be working today. Better clear my cache.

Found another boot disk image from a Mr. Hiren - with rootkit killers and AV on. However there doesn't seem to be anywhere to download it on their site. :C

Here's an alternative download.

Edit - 'Course this is assuming you've got an optical drive in the machine and it's setup to boot from it somewhere in the boot order before the hard drive.

Can you F8 to boot to a command prompt and then do format c:? that'd get rid of it!

(or from a Windows CD, as I imagine you probably can't format the drive the OS is running from.)

I've generally found a clean reinstall is faster, easier and more reliable than trying to av through it. The severity of the issue suggests it may have been root kitted.

I wanted to avoid that due to some software we probably don't have media for but I think tomorrow I'm going to wipe it and start from a clean install. My preferred option every time.