1

I just had Windows 7 swap drive letters around on me, the end result being that the system no longer boots. There are several volumes mounted in the system, so I'm not sure exactly what has changed, but at a minimum the following letters:

C: (500GB SSD, Windows 7 install)
E: (2TB RAID-1, used for storing videos, photos, misc. media files, etc.)
K: (128GB SSD, used for installing whatever game I'm currently playing)
?: (old HDD that used to have some previous version of Windows on it, not sure what letter it used to have, think it may have been D:)

...have become:

C: (old HDD that used to have some previous version of Windows on it, not sure what letter it used to have, think it may have been D:)
E: (500GB SSD, Windows 7 install)
D: (2TB RAID-1, used for storing videos, photos, misc. media files, etc.)
F: (128GB SSD, used for installing whatever game I'm currently playing)

If I had to speculate on a trigger, I recently deleted a partition on the RAID-1 volume and used its space to increase the size of another partition on the same volume. Everything seemed to work fine after I did that (a few days ago), though I didn't reboot immediately afterward.

I rebooted today, and after showing the Windows logo for a few seconds the screen went blank and the machine just sat there, doing nothing. A subsequent reboot brought up the automatic Windows startup repair tool, which said it couldn't do anything. I told it to bring up the manual console, and that's when I noticed that the drive letters had been switched around.

I found some instructions here about how to manually reassign the drive letters, and gave it a try (I was quite surprised to find that the registry editor is actually available in recovery mode). However it doesn't seem to have done anything.

So I think the main problem is that C: is now E:, and it probably also doesn't help that the thing that's now on C: used to have some version of Windows installed on it.

Anyways, the question is, what could have caused this, and more importantly, how can it be undone?

2 Answers 2

1

Okay, problem solved by following the instructions here:

http://www.sevenforums.com/tutorials/163216-bootrec-exe-tool-how-use-windows-recovery-environment.html

To summarize, go to the System Recovery command prompt, and then run the following commands:

  1. bcdedit /export C:\BCD_Backup
  2. c:
  3. cd boot
  4. attrib bcd -s -h -r
  5. ren bcd bcd.old
  6. bootrec /RebuildBcd

I repeated the sequence for both C: and E:, and at the end I also ran a bootrec /fixmbr for good measure.

After that Windows booted normally, and all of my drive letters appear to be correct again.

0

Remove power from all drives, except the one you have Windows installed. When you power on it will take letter C again. Then shut down and connect power to all drives.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .