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Windows 7: Changing C: partition (Boot) from Primary to Extended

26 Oct 2012   #1

Win7 64 bit
Changing C: partition (Boot) from Primary to Extended


(yes I know, "yet another one on this subject" , but please bear with me...)

I am trying to create logical drives, and to that end have to turn a primary partition into an extended one.

Currently I have four Primary partitions (yes, you see it coming... ):
*: SYSTEM (no drive letter, marked System, Active),
C: (no name; marked Boot, Page File, Crash Dump),
D: Recovery, and
*: HP_TOOLS (no drive letter)

I am following (of course) the excellent and rightly famous tutorial here,
and I have to use "Method Two", because I am in exactly the situation described there, namely that the manufacturer (HP) greedily has created four primary partitions already, so that I cannot simply add another one. (And I don't want to touch, let alone delete, SYSTEM and/or Recovery).

The problem is that I was trying to use not the Partition Wizard mentioned in the tutorial, but a similar tool called EaseUS Partition Master.

However, when I told it to turn the Primary C: partition into an Extended one, it refused on the good grounds that this is the Boot partition and can therefore not be touched.

It makes sense, and I am "almost" certain I understand the reason, but before I do something stupid*, I'd like to have this confirmed by someone who knows this stuff better...
(My confusion stems from the idea, apparently wrong, that Active partition means the same as Boot partition; so with SYSTEM as the Active partition, I was kind of surprised to find that actually C: is Boot.)


1. The essential difference seems to be that EaseUS Partition Master is run within a "normal" Win7 session (i.e. having booted from the hard drive), whereas for using the Partition Master (as per the tutorial) one apparently must boot from a CD.
Is this understanding correct?

2. Does that mean that the C: partition in the latter case (booting from CD) is not the Boot partition, and therefore can be changed to Extended (without reformatting, of course)?

3. When I afterwards boot "normally" from the hard disk again, will C: then operate OK as Boot partition (or rather volume now) again, even though it is now a logical volume on an Extended partition?
(This is the question that worries me slightly. There are numerous threads here about this "all primary partitions taken" issue, and I must have read them all; but I couldn't find a clear answer to this last question.)

All this is actually made rather clear in the tutorial, at least implicitly (see e.g. the last screenshot, under Step 4 of Method Two); but I'd still appreciate some explicit confirmation.
It's not my own laptop I am setting up, you see, and I'd hate to mess it up...

Many thanks for your time and help!


* I do already have (via MacriumReflect) an image of all partitions, plus the corresponding boot CD, though

My System SpecsSystem Spec

26 Oct 2012   #2

Microsoft Community Contributor Award Recipient

Windows 7 SP1, Home Premium, 64-bit

I don't know about EaseUS.

Yes, if you use Partition Wizard boot disk, it will operate outside of Windows.

The system partition is the partition containing your boot files. Boot partition is the partition currently booted---C in this case. Boot files are typically not on C in a standard installation, but can be placed on C if desired. That's where mine are.

It's OK for C to be logical. It's one of the ways to get around the 4 primary partitions maximum issue. Logical partitions are not primary.

I'd advise you to use Partition Wizard bootable disk.
My System SpecsSystem Spec
26 Oct 2012   #3

Win7 64 bit

wow, that was quick, thank you!
The system partition is the partition containing your boot files. Boot partition is the partition currently booted---C in this case.
That's what threw me off balance, I naÔvely thought the Boot partition is where the boot files are... Not so, apparently

Will now use Partition Wizard with boot CD.

Thanks again.

UPDATE to report success:
All went well. After booting from the Partition Wizard CD, C: could be changed into an Extended partition, then shrunk as required*, and two new logical volumes could be created.
Thanks again for the help!


* Bonus info (slightly off topic):
When trying to shrink C:, I ran into the well-known (search this forum) issue of "unmovable files" which Win7 apparently chooses to place in the middle of the free space. You can then only shrink down to that location. In my case, the maximum shrink size was therefore only half of the actual free space on C:

Solution: defragmenting C: with the tool PerfectDisk Free (a tip also found on this forum).
After that (even without rebooting), shrinking by up to all of the free space was possible; apparently PerfectDisk had moved the blocking files elsewhere, to a less interfering location.

Minor Caveat: PerfectDisk will defragment C: immediately after installation, without asking permission to do so. I would prefer it to ask me
first, or at least to run only an analysis, but not start messing about with C: at once...
Still, no harm done, and shrinking impediment solved.
My System SpecsSystem Spec


 Changing C: partition (Boot) from Primary to Extended

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