Windows 7 - Drive letters

are the drive letters assigned in the Disk Manager already valid at boot time? I always thought the system uses those drive letters only once Windows is running. However, they are apparently also used by the boot loader and boot manager. Are these drive letters assigned in the Disk Manager stored on the disk, and not just shorter names for the longer diskx/rdiskx/partitionx annotation used by Windows?

the driver letters are OS specific, bootmanager shows the letters as you have them assigned, however the partition the OS is installed on is ALWAYS C:\

example: lets say you have a dual boot of Windows 7 (which we will call OS1+OS2) and the bootloader is stored on partition 1 along with OS1, and OS2 is on Partition 2, (for this example im going to pretend you dont have a DVD drive to simplify the letters)

When you boot into OS1 and run editbcd from command prompt it will show the following: bootmanager is on C OS1 is on C and OS2 is on D

However if you booted into OS2 and did the same, it would say OS2 is on C bootmanager is on D and OS1 is on D

to answer your original question, the letters you see in the bootloader options are what windows reads them as, and the letters arent fixed

hope that was clear enough

The drive letters are assigned by the Windows that boots. For instance, I have Windows7 that sees itself as C: and I have XP that sees itself as H:. But when I boot Windows7 it considers the XP system partition to be D:.

Here is an example of my setup. You see C as the active OS (in this case Windows 7) and E is the OS partition for my Vista (C when Vista is active) and G is the recovery partition for Vista (D when Vista is active) - confusing, isn't it. H, O and P are external disks. N is a data partition shared between Vista and Windows 7 and F is a "catch all" partition that I use for storing temporary stuff.

thanks for the help guys. My situation for me is as follows. - I have two drives, OLD and BIG. - OLD has one partition, and carries drive letter D in Windows (I assigned this). - BIG has two partitions, which I have assigned the drive letters C (partition 1) and F (partition 2). - C has the OS, D has the Bootmanager installed. If I look at the hard disk configuration at the command prompt (without booting into Windows), - C is actually OLD, - D is BIG2, and - F is BIG1. Now I wonder, if I put the Bootmanager into BIG2 and disconnect OLD, will the Bootmanager be found during startup, or would I have to reassign the drive letter in using BCDedit. I know, I should simply try it. But I'm old fashioned and like to hear some advice first. Thanks a lot for the help guys!

i think what will happen is it will lose it and you will have to run startup repair 3 times from your windows 7 disk to fix it, im not entirely sure though

Is D disk0 in Disk Management? It would help if you posted a pic of Disk Management.

Thanks again for your help. Yes, D is Disk0, and C and F are on Disk1 in Windows Disk Management. But at the Command Prompt, what was D in Windows is now C, what was C in Windows is now F, and what was F in Windows is now D. I have the Boot Manager on Disk0 (as assigned in Windows, Windows put it there because I was careless during installation, I wasn't aware what would happen). But I want it on Disk1/Partition1 instead, while the OS resides on Disk1/Partition1. Then I will disconnect the current Disk0, as I'd like to have only one disk in the system (less noise). So I would use bcdedit /set {bootmgr} device partition=X, where X should be the current partition Disk1/Partition2, as seen as by the Windows boot code. Since this is the active partition, I would have guessed that it must be C at the CMD prompt. My current BCD points to D as Disk0, but to Disk2/Partition1 as C (that's where the OS is, not the bootloader), so apparently it uses the Windows drive letter assignment partly, but not everywhere (hence making me think it is pure coincidence). So I am confused what to tell bcdedit as X.

Apparently the MBR was assigned to D because that was Disk0.

do you think the way for me to go would be to use fixmbr with only the big disk connected (starting from the system repair disk)? Or should I try to simply run the system repair a few times with only the big disk connected and see what happens?