How can I change a drive letter from outside of the OS?

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LordJaffa

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Long and short of this is that I cloned an install of Windows 7 onto a larger partition, but the new partition has taken the drive letter "i" as opposed to "c", meaning that every single reference or shortcut is now obsolete, meaning that even my user account is messed up.

Very silly mistake to make, I understand, but does anyone know how it would be possible for me to Force Windows to recognise this drive as C? (The original C partition is no more, the thing booted up fine until I deleted this partition, which is what informed me that the references were still linked with C)

The only bootable disk I have in my possession is the bootable version of the Windows 7 RC disk and the command prompt won't even let me access Fdisk. Any suggestions would be great, because I've really come unstuck here.

Thanks in advance.
 
I can get into safe mode, but again it's just creating a temporary account.. I used diskpart to try change the drive letter, but as it's registered as the boot drive it won't let me reassign the drive letter.

Is there any way to override that block perchance?
 
LordJaffa said:
I cloned an install of Windows 7 onto a larger partition, but the new partition has taken the drive letter "i"
Click to expand...
When you boot to it (the OS that has been cloned), or when you boot to a different OS?
Did you clone the hidden 100MB system partition as well?
 
When I boot to the new installation, it says that the system partition (the one that 7 puts the windows logo next to) has the drive letter "i".

I'm currently dual-booted to my XP install, and it's called the new volume "G"

I'm going to go out on a limb here and say that I didn't clone the hidden partition, I used Clonezilla from a live CD and simply duplicated the original Windows 7 partition.
 
1- Do you still have access to the original OS?
2- If yes, can you boot to it and using disk manager find out where the system partition is?
It is either on a hidden partition, or it is on the same partition as Windows 7 depending on how you made the original install.
3- Boot to the new install that is now on drive i and use the disk manager and see where the system partition is.
 
Now, I don't know if this will work on Win7, but look at http://www.goodells.net/multiboot/partsigs.htm.

The "SavePart" utility they mention is on Hirens and other boot disks, runs outside of any OS, and lets you map drives, letters and partitions in the registry by DiskID.

Other than my uncertainty about the Win7 registry structure, it would do exactly what you need. Been there, done that, when cloning and at other times. I've moved my original XP install all over between different disks, partitions, different partition order, and had to use the tool at one point because I accidentally allowed the OS to see both cloned drives (which they mention in this article). Savepart let me remap things at will.
 
This problem is caused when you either format/mount the drive before you clone it or if you mount the drive while still running from the original drive. In both cases it creates an association between the drive letter it is mounted with and the drive's windows-generated serial number.

Try this: boot with the 'old' OS drive. Mount the cloned drive. Now open 'computer management' and go to the 'disk management' function. Right click the cloned drive and select 'change drive letter'. You can't change it back to 'C' with the old OS running, but you can change it to have no drive letter at all. Close everything up, shut down, remove the original OS drive (it can't be on your system at all) and re-boot from the clone. All should be well.
 
PigLover said:
This problem is caused when you either format/mount the drive before you clone it or if you mount the drive while still running from the original drive. In both cases it creates an association between the drive letter it is mounted with and the drive's windows-generated serial number.

Try this: boot with the 'old' OS drive. Mount the cloned drive. Now open 'computer management' and go to the 'disk management' function. Right click the cloned drive and select 'change drive letter'. You can't change it back to 'C' with the old OS running, but you can change it to have no drive letter at all. Close everything up, shut down, remove the original OS drive (it can't be on your system at all) and re-boot from the clone. All should be well.
Click to expand...

In my case when I made the error I mentioned in my previous post, the cloned system started to freeze just before the login screen because some parts of the OS couldn't make sense of the mapping for the DiskIDs.

I do not believe what you're suggesting will work.

The DiskID <-> Drive Letter mapping is in the registry of the running OS. Making the change you suggested simply changes registry entries on the old OS, it doesn't change any partition or labelling information on the cloned partition at all. The new OS registry will still be wrong.

This is why SavePart (or similar) is required to edit the registry of the target OS(s) while they are offline.

As the article I linked to stated, never have the old and cloned partitions visible to the OS at the same time during the process or you'll be in trouble with partition/letter mapping and DiskIDs (and possibly even booting at all depending on the situation).
 
Surly, you've made my day!

The link you gave me had a (believe it or not) link to the MICROSOFT website giving instructions on how to manually alter the registry-defined drive letters. Simply found the appropriate drive letter and renamed it to be "C".. One short reboot later and everything's as it was (With the additional 20GB of partition space that I was so sorely lacking in the first place)

Many thanks my friend, problem solved and case closed :)
 
LordJaffa said:
Surly, you've made my day!

The link you gave me had a (believe it or not) link to the MICROSOFT website giving instructions on how to manually alter the registry-defined drive letters. Simply found the appropriate drive letter and renamed it to be "C".. One short reboot later and everything's as it was (With the additional 20GB of partition space that I was so sorely lacking in the first place)

Many thanks my friend, problem solved and case closed :)
Click to expand...

Well, yes, you could always do it by hand ;)

I had a number of drives to remap and didn't relish the possibility of data entry error so I used a tool.

Happy to have helped...
 
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