Reinstalling WinXP hosed my drive letters...

January 10, 2009 11:50 AM

WTF? I thought I knew what I was doing! I reinstalled WinXP on C:\ and it screwed up all my drive letters and made a secondary partition into a system partition. Help me get it back to normal!

Here's how things were before I screwed it up:

HDD0 - WD 160GB
C:\ - WinXP OS (30GB)
D:\ - Data (My Docs, music, etc) (120GB)

HDD1 - Seagate 160GB
E:\ - Backup

I made sure I had all my ducks in a row and the reformatted C:\ and reinstalled Windows. When I got into Windows I noticed that the 'D' and 'E' drive letters had been switched. All the data is still present and accounted for. I went to rename 'E' back to 'D' and noticed that 'C' is designated as a Boot partition and 'E' (which should be 'D') is designated as a System partition, so I can't change the drive letter.

I'd love to know how this happened but I'm much more interested in how to fix it. How do I make 'E' back into a non-System partition without putting the data in jeopardy?

posted by jluce50 to computers & internet (7 comments total)

I can't help you with the restoring of the data partition to non-system, but I'll suggest a workaround:

If there's no application that relies on backups being on E, or otherwise uses that partition, then you can simply add 'D' as a drive letter for the data partition, after you have assigned backup to another letter like 'F'. If you do this, then 'D' and 'E' will both refer to the data partition, and both can be used.

Strange thing is, I tried this on my comp XP SP2, right now to see if it still works, but it's not allowing me to assign a 2nd letter to any of my partitions. I had done this earlier when I had issues with a problematic customised XP install. If it doesn't work for you, you can just use subst from the command line.
posted by Gyan at 12:20 PM on January 10

Do Start --> Run --> compmgmt.msc

That opens the Computer Management utility. You should see a Disk Management item on the list on the left. Select that, and you should see a list of your current volumes and partitions appear on the right. You can rename any drive--except C--with any unused letter you like.

This won't let you change the actual properties of the partition, you'd probably need something like Partition Magic for that, but changing drive letters is easy.
posted by valkyryn at 12:40 PM on January 10

You probably chose the wrong partition during windows setup. It looks like your old C: drive is there and the bootloader is pointing to the windows install on E:

Backup your data and start over with the windows disc. When you get to the partition screen, delete ALL partitions. **This will delete everything, so make sure you really backedup** Then make a big fat juicy one for C:. Let the installer just put everything on C:.

If you need a second partition do it that screen but make sure you are installing windows on that first big partition.

Diskmanager wont be able to change letters on the system drive. Thats the partition you are currently running windows off of.
posted by damn dirty ape at 12:51 PM on January 10

@damn dirty ape: That's more or less what I figured but all my data was still on the second (System) partition. If it had installed windows there it would have wiped all that out. Not to mention there were none of the windows directories on that partition. I didn't think it possible, but it appears to have reinstalled Windows on the Boot partition and marked the other partition as the System partition. Very weird.
posted by jluce50 at 12:58 PM on January 10

Counterintuitively, the boot partition does normally refer to the location of the OS, and the system partition, the location of the bootloader. You should see NTLDR and NTDETECT.COM in the root of E, if you can see system/hidden files.
posted by Gyan at 1:08 PM on January 10

Crap like this is why the standard advice for Windows reinstalls on computers with more than one hard disk involves unplugging all the drives except the one you're installing to. Windows is a pig.

If I were in your shoes, I would be unplugging the E: drive and seeing if Windows still boots. I expect it wouldn't, because I expect that the idiot installer has written the boot loader to the wrong drive. So then I'd swear at it, and use the FIXBOOT and FIXMBR commands in the recovery console to see if I could make it boot without the E: drive. Only when I had Windows working again with just the single drive plugged in would I reconnect the E: drive and then play with drive letters in Disk Management.
posted by flabdablet at 3:16 AM on January 11

I ended up doing basically what damn dirty ape suggested. After copying all my data off of 'E' I deleted and recreated both partitions on HDD1 and then installed Windows on 'C'. Everything seems to be okay now. I've got everything more-or-less the way I like it and I'm in the process of creating an image of 'C' so I never have to go through this again. Now once a year or so I'll just reformat and restore from the image and everything will be right with the world.

Thanks for the suggestions!
posted by jluce50 at 7:58 AM on January 11