I recently chose to migrate from the 1Tb spinning disk to a 128Gb m.2 + 1Tb HDD, with OS & programs installed on the m.2 and data on the HDD.

I didn't have time to do this as a dedicated task, so needed to keep the previous Windows 10 Pro installation on the old drive to use while I got the new OS set up in my spare time. Coincidentally the previous installation was 32-bit, whereas the new one is 64-bit. This all went off without a hitch, I ran both OS in parallel, got the new one set up and configured, and decided that I'm ready to delete the old installation and clean the 1Tb drive so that it's ready to become a data drive.

Unfortunately I then discovered the System Reserved Partition on the HDD.

Current state

Currently my drives are partitioned like so:

  • Disk 0: [500mb System Reserved] [931Gb NTFS; old OS]
  • Disk 1: [119Gb NTFS Bitlocker Encrypted; new OS]
  • Disk 2: [14.91 OEM Partition]

Disk 2 is another m.2 which was included with the machine as a cache drive.

I want to move the System Reserved partition off the 1Tb drive, partly for neatness and to allow me to swap-out the data drive if desired, and partly for boot speed (by putting it on an m.2). Since the cache drive software for Disk 2 is incompatible with Bitlocker, and since I'm running most functions from an m.2 anyway, I'm perfectly happy to format Disk 2 - it seems like a prime candidate for the System Reserved partition. Especially as I would rather not mess around with resizing the Bitlocker-encrypted partition.

My question

So, my question is:

Given that the System Reserved partition is very important (my main OS is currently encrypted, but could be decrypted for this process if necessary); and I don't want to go through another clean install if at all possible...

Is it possible to simply move the System Reserved partition in place to the small m.2, and completely clean the HDD? Would moving it like that affect boot and/or Bitlocker? If so, what is the best way to accomplish it - would I need to disconnect the HDD and repair the installation or something like that? Would I need to decrypt first?

Thank you!


In case it's helpful to anyone in future, I did resolve this, with a lot more effort than I had hoped to spend! The basic process was:

  1. Decrypt C: drive;
  2. Shrink C: partition by 500mb at beginning of drive; Copy System Restore Partition into unallocated space (I used MiniTool Partition Wizard for this). Mark it as active;
  3. Use EasyBCD to ensure it is set up to boot into the OS, and restart to test;
  4. Delete System Restore Partition on HDD, and expand the remaining partition to fill the unallocated space;
  5. Run Windows 10 installer from within Windows, 'installing' the OS, but keeping programs and files - this will repair the manually created System Restore Partition properly;
  6. Re-encrypt with Bitlocker.

Hope this is helpful! Long and the short of it is: try and think of these things before you start...

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.