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My computer was installed from a USB stick, and now the Windows' drive is D:, while C: is used for external media.

I'd really want/need to change, so Windows & Program Files' drive letter will be called C:, and D: is left for something else (2nd partition).

How can I do that? Simply forcing drive letter change will cause window's internal links to break. There should be an ordered procedure or a software that does it.

I don't mind re-installing Windows for that matter, but I don't know how to force setup to call it C:

When i set windows up in the 1st place, the partitioning screen referred to the target drive as C:, but the end result is D: :(

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You'll have to reinstall windows either from a CD, or follow an installation guide that takes the flash drive into account.

There's no easy way to change it after the fact, especially since the drive paths for all the applications would also have to change.

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If you need it to be C and it is currently D, three steps.

  1. First, force the C, or use a partition editor to do so actively.

  2. Then export your entire registry as a text file, and replace all D:\ with C:\ (Replace all command),

  3. Then import back into your registry to replace it and restart.

Now you'll need the disks or installers from all your programs, but you should be able to "Repair" them and have any of their config files rewritten to enable the programs to function without a problem (you might need to simply reinstall).

My Documents etc will be fixed, the rest should work. It's a long and grueling process, but in the end you should have everything you need. If a driver malfunctions, reinstall it, and you should be fine. Most of them use Reg keys to store linkage, so once you fix that, it will write to a config file when the driver is used.

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The boot drive is always called C, so your setup probably contains two partitions, where C is the boot disk and D is the system disk.

To undo this setup, you will not only need to reinstall Windows, but also to erase and re-create during the boot all the partitions, so that their drive letters are re-allocated.

Dividing the hard disk into two partitions, system/applications and user-data is a good idea, but there are two considerations:

  1. The system/applications disk must be large enough (for Vista/7 I would make it at least 40 GB, and if installing monsters like Visual Studio then 60 GB)
  2. To avoid drive letter problems, during the boot create only the system/applications disk, creating the data disk from inside the installed Windows.

Of course, nothing stops you from erasing all partitions and allocating the whole disk as one partition. Just beware not to erase the manufacturer's restore partition (if you have one).

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actually, that's what i did! i erased the partition table, and created it within windows' setup. somehow because the usb drive was automatically assigned the letter C:, nothing else mattered. – Berry Tsakala Nov 29 '10 at 7:57
If that's the right answer, you should mark it so, for future generations. – harrymc Nov 29 '10 at 9:10
pardon: that's what i've dont so far, without results – Berry Tsakala Dec 1 '10 at 7:17
Incomprehension: are you booting from USB? – harrymc Dec 1 '10 at 8:18
"The boot drive is always called C" False. This was required in Win9x, but not in NT versions (of wish 2000, XP and newer are part.) – nitro2k01 Mar 12 '12 at 5:01

You don't mind reinstalling Windows? Then change D:\ to C:.. Windows will most likely break. Go to setup for Windows, and C:\ should still be C:. Format D:\ and C:\, and then install Windows on C:. Once that is completed, you can log into windows and delete D:\ of you wish. This is, atleast, how I would handle this.

Thanks to someone reviving this question from two years ago, I thought it was new and didn't realize it was from 2010.

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