Shrink disk partition in Windows Server 2012

Updated on: November 16, 2019

This article introduces how to shrink partition in Windows Server 2012 R2 without losing data. Shrink drive with Disk Management and partition editor.

Shrink partition in Server 2012 Disk Management

When you want to shrink an allocated partition to create new drive, you can achieve without third party software. Windows Server 2012 Disk Management has Shrink Volume function, which can decrease partition size without losing data and on the fly.

It is very easy to shrink partition via Server 2012 Disk Management:

  1. Press Windows and X on keyboard and select Disk Management from the list.
  2. Right click the partition and select Shrink Volume.
  3. Enter an amount of space and click Shrink.

Disk Management can only make Unallocated space on the right side.

Shrink partition

Can't shrink partition in Server 2012 DM

In some servers, Disk Management cannot shrink partition or give you little available space to shrink. In most cases, it caused by "unmovable" files. Another possible reason is File System error.

In my test server drive D: is blank, but Disk Management gives me only 19417MB (18.96GB) available space in the shrinking window, so I can only shrink D drive to 31.04GB.

Cant shrink

In some server or PC, Disk Management can't shrink volume for even 1MB. I've encountered such issue before in my Windows 10 computer.

Can't shrink

As the tip in the shrinking window, you cannot shrink a volume beyond the point where any unmovable files are located.

The unmovable files include Paging file, Hibernation and other large files. If any type of unmovable files are located in block 3rd, you cannot shrink this partition to block 2nd or 1st, although there is free space there.

Unmovable files

Only NTFS format partition is supported, Disk Management can't shrink FAT32 and other types of partitions, no matter whether there are unmovable files.

Shrink drive with NIUBI Partition Editor

Comparing with Server 2012 Disk Management, NIUBI has advantages while shrinking a partition:

Download NIUBI Partition Editor and you'll see all disk partitions with structure and other information in the main window.

NIUBI Partition Editor Server

How to shrink partition in Windows Server 2012 with NIUBI:

Right click drive D (or other one) and select "Resize/Move Volume", you have two options in the pop-up window.

Option 1: If you drag left border towards right

Shrink rightwards

Unallocated space will be make on the left side of D.

Volume D shrank

Option 2: If you drag right border towards left

Shrink leftwards

Unallocated space will be make on the right side of D.

Volume D shrank

Shrink partition D to expand C or E

If you want to extend other drive by shrinking a partition in Windows Server 2012 Disk Management, it is impossible, because Disk Management has serious restrictions:

  • Unallocated space can't be made on left side when shrinking a drive (such as D:), so It is non-adjacent to system C: drive.
  • Extend Volume can't combine Unallocated space to any non adjacent or the right contiguous partition (E:).

As you see, Extend Volume is disabled for both C and E drive after shrinking D.

Extend volume disabled

If you want to extend partition in Server 2012 by shrinking other volumes, NIUBI Partition Editor works well and easily. Follow the steps in the video:

Video guide