How to switch/rename boot partition to keep it as C: different drive

dimitrifrom31 · 26 Jul 2014

Long Story short I got a laptop with an HDD where I originally installed windows 7 (on C:).
I purchased an mSata SSD drive and cloned the HDD to the mSata as I would like to use it for OS and most used programs (for obvious performance reasons).

Now I got:
Boot set to Disk0 Partition C:\ (HDD)
and a clone of the C:\ partition labelled X:\ (mSata)

What I would like to do:
- Boot on the mSata (currently X:\)
- Ideally rename X:\ to C:\ and rename C:\ to anything (or just format it once Im sure everything is good).

What I did/tried:
I have read several threads about similar operations but none is matching my case as I am having a clone copy with a different letter and would basically "just" need to rename the drive letter and change the boot.

In Bios I have set it to boot to the mSata drive in priority but it appears to keep booting on C:\.
It douns quite simple but ends up being quite complicated.

edit: post #3 seems to have worked: Changing Win7 System/Boot Partition without Reinstall

gregrocker · 26 Jul 2014

Post back a screenshot of Disk Management - Post a Screen Capture Image.

Win7 should always boot up as C drive no matter which one you're booting in a Dual Boot like that. If not I'd clone it again this time using the Auto drive letter setting, carrying over the Active partition (System Reserved?) on the source HD, MBR and Track 0 if those choices are offered. Then all you need to do is change the HD set to boot first in BIOS to start up the clone and it should boot as C.

If not let us know what options are available for cloning, and let us see the screenshot of both drives now preferably booted into the new OS if possible.

AddRAM · 26 Jul 2014

Even if it was X, which it shouldn`t be as Greg has stated, you just can`t change an install partition letter, it would render your system useless

SIW2 · 26 Jul 2014

He hasn't changed the os registry letter. It is a clone.

Looks like he has fixed it:

3

LMiller7 · 27 Jul 2014

How drive letters work:

Partitions themselves have no concept of drive letters. Nowhere in the partition is there anything that specifies what drive letter it is. Back in the days of DOS when partitions were first devised drive letters were assigned by a fixed set of rules. A drive letter was what it was and there was no way to change it directly. This was simple but had some drawbacks. A big one being that installing a new physical drive could change existing drive letters and there really was nothing much you could do about it.

That changed in NT. Drive letters are assigned in the registry. When you set drive letters in Disk Manager that is what it is doing.

dimitrifrom31 · 27 Jul 2014

Indeed, C: and X: were 2 clones. I applied the commands given in the link mentionned and it made my X: become C: and vice versa.
Anyway my laptop has then booted from the mSata drive which was my goal and I formatted the HDD to use it as secondary drive.

gregrocker · 27 Jul 2014

Those instructions you followed make the clone bootable on its own so when you set it first to boot in BIOS it will boot. It was already cloned as C but only seen as X in the old OS"s Disk Mgmt or WinRE. As Brian pointed out you can't change an OS letter once assigned without ruining it.

It would still be good to see the Disk Mgmt as I'd requested since about half the time we spot something awry.

dimitrifrom31 · 28 Jul 2014

That's how it is now , note that I have formatted the "new" X: and renamed it to G:
http://puu.sh/aueqn/c4fbc8d48e.png

AddRAM · 28 Jul 2014

Looks Good, I didn`t even know I could read French

oui oui misure

gregrocker · 28 Jul 2014

Looks OK, but be aware that you must unplug the other hard drive whenever you do a reinstall or Startup Repair or it may derail the System partition to the first Primary partition in order.

For this reason its best to have the OS in DISK0 position, by swapping the cables and resetting it first to boot in BIOS, if possible.