How can I change which partition is the system partition?

[Anonymous]

I was running Windows Server 2012, and installed Windows Server 2012 R2 in a separate partition. Knowing it would take several days to get around to installing and tweaking all my software, I set it up as a dual boot. Both partitions are primary partitions and are bootable partitions. 2012 is the system partition.
I have physically moved things around so that 2012 R2 is now at the front of the drive, and 2012 follows immediately after.
When I’m booted into 2012 R2, it calls itself the C: drive. Likewise, when I’m booted into 2012, it calls itself the C: drive.

I’m now ready to move exclusively to 2012 R2, and would like to recover the space used by 2012. But I can’t delete it, because it’s the system partition. I tried, and it rendered the system unbootable. Of course I had saved an image, so it was a simple thing to restore it back to life. But that’s not a long-term solution.

QUESTION: How can I make 2012 R2 the system partition instead of 2012?

I’ve attached a screenshot of the hard drive setup.

Here’s what I’ve tried so far:
1) EasyBCD: BCD Backup/Repair – Change boot drive to 2012 R2. Still doesn’t boot if 2012 is absent.

This question is not specific to Windows Server 2012. In fact, the question would apply to any dual boot setup, and I would expect this to be a common scenario. But I have searched in vain extensively on the internet for help with this. I find lots of places which tell me how to switch the active partition. But not one — nothing! — on how to switch the system partition.
Most of the help sites advise rebooting with the install DVD, and going to “Repair.” The problem there, of course, is that Windows Server installation DVDs have paltry repair tools.

Thanks for your help!

[Anonymous]

OK, I solved it myself.
Although I used TeraByte’s excellent but not well-known program BootIt Next Generation (which has been superceded by BootIt Bare Metal), so this may not be helpful to many people.

I booted with BootItNG, and from the Partition module deleted the 2012 partition. I then clicked “View MBR.” Faced with bewildering array of data and options (I’m not a techie), I clicked “Make Active” and crossed my fingers. It did the job!

TeraByte has been making partition and boot software for twenty years. They’re “old school” in the sense that most of the work is done outside of the OS — that is, they boot their own OS to do work on the system, just to be absolutely certain to avoid conflicts. I still think they’re one of the best in the business.
They offer a free 30-day trial of all their software, so how can you go wrong?

[Author]

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