XP won't boot after virus problem.

Zaph0d

An elderly relative of mine rang me up with a virus infected win xp machine. He had opened an email attachment faked to look like it had come from his ISP. The attachment was in a stuffit archive and he even bought stuffit to open it!

I put his hard disk in my machine as a slave (I set the jumpers first) and virus cleaned it with avast. There was some variant of mydoom on it in a file called external.exe.

this is the virus:http://sophos.co.uk/virusinfo/analyses/w32mytobat.html

Then I set the jumpers back to CS and returned it to the original (Dell) machine. When I turned it on it said something like 'Non bootable disk error'.

The disk is visible in the bios. I can start the machine from the winXP install disk and run the recovery console.

I've tried setting the jumper to Master. There are no other HDs in the machine, just a DVD drive on the second IDE channel. I'm fairly sure the HD was originally set to CS.

What makes a disk bootable? Is it having an NTLDR file?

I suspect that the disk is fine and I am just doing something very dumb. Any suggestions? Should I just get the data off the disk and reinstall it?

One thing I couldn't do with avast virus cleaner was to clean an inactive/offline registry. This would be a really useful feature, because obviously it's best to clean disks when they don't have a live OS running on them. Anyone know a tool that can do this?

Orion

Dell do set hdd's to CS as a general rule so you're right there. You could try and do a repair on the installation. Boot from an XP cd and select repair when given the option. This should replace the boot files on the disk.

Mixie

If all else fails, fixboot and fixmbr from the recovery console.

Webmonkey

^ Yep bout to mention that

Oriel

Aye, basically the computer knows that the hard drive is there, but doesn't know where to look for the windows startup.

Mac daddy

yep as said by mixie -boot of the os cd's run a fix master boot record fixmbr fixboot - It could have been overwritten when you installed the hdd in your comp -

Zaph0d

Thanks a lot for the answers. I know very little about PCs.

I was worried to run fixmbr in case it made the disk unreadable.

I didn't know that putting a disk in another machine could change the mbr.

anyhow cheers to all of you.

Mixie

No problem. If it helps to put your mind at ease neither fixboot or fixmbr have ever caused me to lose data/etc. In fact, I can't recall a time when they haven't worked perfectly (and you'd be surprised at just how often I need to use them!)

Webmonkey

Mixie wrote:

No problem. If it helps to put your mind at ease neither fixboot or fixmbr have ever caused me to lose data/etc. In fact, I can't recall a time when they haven't worked perfectly (and you'd be surprised at just how often I need to use them!)

Yes it won' cause much harm

Orion

fixmbr is the NT equivalant of FDISK /MBR. It just rewrites the master boot record and doesn't touch any data at all.