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Windows 7: 100mb partition on non-system disk

20 Jul 2010   #1

Windows 7 Professional (x64)
100mb partition on non-system disk

My current setup is Windows 7 Professional on a 64Gb SSD, and my data on a 1TB HDD; I wish to upgrade my data storage to RAID 5 (via Intel Matrix RAID).

Whilst examining my HDD before I make the change, I noticed that it had a system reserved partition of 100MB on it. After a lot of googling, I had determined that this is used for BitLocker and system recovery, and is not (in most cases) necesarily needed.

However I think that my situation may be different.

The complication is that the system reserved partition is marked as 'System' (as can be seen in the below screenshot), and it seems (from changing boot orders) that the OS actually bootstraps from the 1TB HDD (although it resides on the SSD entirely).

Clearly this is non-ideal (unnecessary coupling of data drive to system drive ect ect).

Does anyone have any experience with this, or know how I could safely migrate the System Reserved partition (or just the MBR, as I dont use bitlocker and have the windows install disks) to the SSD?

Thanks in advance for any replies.

Attached Thumbnails
100mb partition on non-system disk-diskmanagement.png  
My System SpecsSystem Spec

20 Jul 2010   #2
Microsoft MVP


Temporarily unplug the data drive, boot the Windows 7 DVD Repair console or Repair CD, at first screen press Shift F10 to open a Command Line then use Diskpart to mark Windows 7 partition active: Partition - Mark as Active
System Repair Disc - Create

Now return to DVD/CD Recovery Tools list to run Startup Repair up to 3 separate times with reboots to write the System MBR to Windows 7. Startup Repair

Afterwards you can plug back in data drive to delete 100mb in Disk Mgmt, or use free Partition Wizard bootable CD to delete 100mb and Resize Data Partition into it. You can also use PW CD to Modify Windows 7 to active instead of Diskpart.
My System SpecsSystem Spec
24 Jul 2010   #3

Windows 7 Professional (x64)

Thanks gregrocker, those steps worked like a charm. Time for my RAID array!
My System SpecsSystem Spec

22 Aug 2010   #4

Windows 7 64-bits

Hi everyone,

Sorry to bring this back up, but this is actually the exact trouble that I'm having! I feel like this thread is so close to giving me the answer, which is why I didn't want to create a new one.
I have tried your fix, gregrocker, but unfortunately it doesn't work...yet! I'm sure there's a way to make things right.

Let me get more into the specifics. I bought a laptop with a 500GB HDD with Windows 7 factory-installed there. I later added a bootable mini-PCIe 64GB SSD drive.
After having added the SSD, I ran an install of Win 7 with both drives plugged in and deleted all partitions from them, before installing Windows 7 on the SSD. Installed and booted well, only problem is that the "System Reserved" partition appeared on the 500GB HDD. If I try unplugging the 500GB, Windows 7 won't boot...

When I ran your fix, gregrocker, I made SSD OS partition active, and after the 3 repairs it placed the system back on the SSD, and let it boot correctly. BUT, when I plugged the 500GB HDD back in, the "System Reserved" partition that was still in there couldn't be deleted, as it was in use and active: the system had in fact booted again from that damn partition!

What I tried so far:

-Installing with 500GB HDD unplugged, which worked to get the "System Reserved" partition on the SSD. The 500GB was completely empty, but when I plugged it back in, the system would still not boot anymore! I ran a repair from disc which got the "System Reserved" partition back on the 500GB...

-Format 500GB HDD with one big partition taking up all the space. In that case, unable to make the System Reserved partition, Windows 7 very intelligently chose to make the whole 465GB partition an active system partition without an assigned letter. Wow, Windows 7 is really good

-I also tried running this fix (fix number 3 was the closest). Didn't work...

I should specify that I run my disks in AHCI mode and that the 500GB HDD is on port 0, SSD being on port 3 (can't change that...).
Any answer would be greaty appreciated! Thanks in advance.
My System SpecsSystem Spec
22 Aug 2010   #5

Windows 8.1 Pro x64 x3 + Windows 10 Preview, Ubuntu

As the system will boot from the SSD when the 500GB is not present - you are almost there

If you have 2 active drives the system will boot from the drive with the lowest ID in this case the 500GB

if you use the partition Wizard disk as listed by Greg, to boot from, to remove the 100MB partition from the 500GB drive, it should then boot correctly though you may need to perform another start up repair to finalise the changes
My System SpecsSystem Spec
22 Aug 2010   #6
Microsoft MVP

W 7 64-bit Ultimate

Hello Rewstah, welcome to Seven Forums!

You could take it a step further and do a wipe to the 500GB while it is the only one connected, this will over-write all the data on the entire HDD and mark it as unallocated space; then do a clean install with only the SSD connected, that should solve it. The bootable CD will do that.

Partition Wizard : Use the Bootable CD

click to enlarge
100mb partition on non-system disk-wipe.jpg

My System SpecsSystem Spec
22 Aug 2010   #7
Microsoft MVP


Or if you don't have the PW CD then use DISKPART from the Windows 7 DVD Command Line to wipe the 500gb HD while only it is plugged in:
Clean and Clean All with Diskpart Command - Windows 7 Forums.URL
My System SpecsSystem Spec
22 Aug 2010   #8

Windows 7 64-bits

Oh man, thank you guys so much for these answers!
Actually, I just got it to work a couple hours ago. I have to admit, though, it was the result of some rather random fiddling with install and BIOS settings, which I still have to make sense of to remember it as a proper method. All seems clean and operational, though, so I won't tempt the devil by getting my hands back in it.
Still, you've been of tremendous help, since I will have to re-install from scratch in a couple months! Thank you so much for taking the time. I'm bookmarking this discussion for later reference.


My System SpecsSystem Spec
22 Aug 2010   #9
Microsoft MVP

W 7 64-bit Ultimate

Hello again, glad you got it sorted; thanks for the update.
My System SpecsSystem Spec

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