computer boots to black screen with blinking white cursor

At this point, there is so much potential corruption that you should reformat the entire HD as a single drive.

Once you have a tweaked working configuration with all your applications reinstalled and data files replaced, [i]image[/i] the HD to an external hard drive with a reputable utility such as Norton Ghost:

http://www.symantec.com/norton/products/overview.jsp?pcid=br&pvid=ghost14

Now that you have a working configuration safely archived, you can repartition the HD with a user-friendly utility such as Partition Magic:

http://www.symantec.com/norton/products/overview.jsp?pcid=sp&pvid=pm80

If you create two primary (bootable) partitions, Windows will assign the MBR (master boot record) to one of the partitions. Ghost can restore the MBR with your archived image should this kind of thing ever recur.

There are a number of things you could do at this point, but I suspect it's a matter of [i]too little, too late[/i]. So I recommend that you bite the bullet, do it right, and hopefully you'll never have to do it again.

I am not particularly expert at command line repairs, but you might consider the following options:

Replace the Boot Sector -

1) Boot computer from installation/recovery CD
2) Press [b]R[/b] to repair
3) At the command prompt, type: [i]fixboot[/i] [drive]

Repair the Master Boot Record -

1) Boot the computer from the installation/repair CD

2) When the text-based part of Setup begins, follow the prompts. Press the [b]R[/b] key to repair a Windows XP Pro installation.

3) To replace the Master Boot Record (MBR), at the Recovery Console commant prompt, type [i]fixmbr[/i]

4) Verify whethe you want to proceed. Depending upon the location and the cause of the corruption within a damaged MBR, this operation can cause the data on the hard disk to become inaccessible.

Alternatively, use DiskProbe to replace the MBR and Partition Table. If you have backed up the MBR by using DiskProbe, you can use it to restore the MBR on any disk that is not used to start the computer. Restoring the backup MBR rewrites the entire sector, including the partition table.

For more infomration about restoring backed up MBRs by using DiskProbe, click [b]Tools[/b] in Help and Support Center and then click [b]Windows Support Tools[/b].

[The preceding was transcribed from the Windows XP Professional Resource Kit (Microsoft Press, 3rd ed., 2005), ch. 28 (Troubleshooting Disks and File Systems), pp 1146-1150].

Rick/Portland, OR

But I would probably go one step further and say wipe the drive so that you remove the Non Windows Partitions that you created and then format the drive with the Windows Installer.

You can get Boot & Nuke to wipe the drive from here

http://tinyurl.com/4rfur

If you don't have a current backup you can use a Live Linux to boot from the Optical Drive and copy your data. I would suggest Knoppix but any will do

http://tinyurl.com/23nmq

Post back if you still have problems.

Col

Until your post, I didn't know about [i]Darik's Boot and Nuke[/i]. This will be a valuable resource. I'll burn it to a CD, and hopefully never use it...

Appreciatively,

Rick/Portland, OR

P.S. - Did you notice the neat avatar created by our fearless pirate CaptBilly1Eye?

But depending on what it was that you used to attempt the Defrag it could have been deleting the files as well. Well not actually deleting them just removing the contents of the file. Or it could be that because the process was stopped the Defrag was not completed and the affected files where going to be moved and now only have the headers left.

Col