Shrink C drive in Windows Server 2008

Updated on: July 11, 2019

This article introduces how to shrink system partition in Windows Server 2008 without losing data. Shrink C drive to extend D or other volume.

Shrink C drive in Server 2008 Disk Management

Better than previous Server 2003, Windows Server 2008 has new Shrink Volume function in native Disk Management tool, which is able to shrink system partition and data volumes without losing data. Better than third party software, it can shrink hard drive on the fly without rebooting server. However, because of some inherent limitations, you may encounter issue while shrinking system C drive.

Steps to shrink C: drive in Windows Server 2008 Disk Management:

  1. Press Windows and R together on the keyboard, type diskmgmt.msc and press Enter.
  2. Right click C drive and select Shrink Volume from the list.
  3. Simply click Shrink to decrease C drive with maximum available space by default or enter an smaller amount by yourself.

In a short while, system partition C is shrunk and 20GB Unallocated space is made on the right side.

If there is plenty of unused space in C drive, but Disk Management gave you little space in the shrinking window, it means that there are unmovable files in this partition.

Shrink Volume C

Shrinking window

There's a tip in the Shrinking C: drive window - You cannot shrink a volume beyond the point where any unmovable files are located.

For example: there's 50GB free unused space in system partition C, if there are "unmovable" files are located in block 3, Disk Management cannot shrink C drive beyond this block to 1 or 2. Therefore, Disk Management only allow you shrinking C drive with free space in block 4.

Unmovable files

This is the reason why many people feedback that there's little space available when shrinking system partition in Windows Server 2008.

Another serious restriction of Disk Management to shrink partition: only the partitions that are formatted with NTFS or without any file system (RAW) can be shrunk. FAT32 and other types of partitions are not supported.

As you see in the screenshot, both Shrink and Extend Volume options are greyed out for drive E, because it is FAT32.

However, it is not an issue to C drive, because most of system partitions are formatted with NTFS.

Cannot shrink

Better way to shrink system partition C

If you cannot shrink C: drive with plenty of free space, because there are Paging file, Hibernation or other unmovable files, you can shrink with disk partition software. As the safest tool, NIUBI Partition Editor can move these files, so it can shrink system partition or any other volume to minimum size (if you want). While shrinking partition with NIUBI, Unallocated space can be made on either left or right side.

Download NIUBI Partition Editor and you'll see the disk partitions with structure and other information on the right, available operations to highlighted disk or partition are listed on the left or by right clicking. There is drive C, D, E and a system reserved partition. Original C drive is 60GB.

NIUBI Partition Editor

How to shrink system partition in Windows Server 2008 with NIUBI:

Right click system C: drive and select "Resize/Move Volume", drag the border towards other side or enter an amount manually in the pop-up window.

Shrink C drive to left:

Drag right border towards left

Drag to shrink

Then Unallocated space is made on the right of C drive.

Shrinkk to left

Shrink C drive to right:

Drag left border towards right

Drag to shrink

Then Unallocated space is made on the left of C drive.

Shrink to right

NIUBI is designed to work in virtual mode, real disk partitions won't be modified until click Apply on top left to confirm.

Shrink C drive to extend D or System Reserved partition

If you just want to create new data volumes by shrinking system partition in Windows Server 2008, you can achieve with Disk Management in most cases. But if you want to extend D: drive or expand System Reserved partition by shrinking C drive, Disk Management cannot help you.

Cant extend volume

As you see in the screenshot, Extend Volume is grayed out for both D drive and the system reserved partition, this is because:

Disk Management can only make Unallocated space on the right while shrinking any partition.

Extend Volume can only merge Unallocated space to the left continuous partition. Drive C is nonadjacent and E is on the right, so Extend Volume doesn't work.

NIUBI Partition Editor can shrink C: drive and make Unallocated space on either side. Unallocated space can be combined to any other partitions in the same disk (except EFI partition in GPT disk).

Follow the steps in the video to shrink C drive and extend D or system reserved partition in Windows Server 2008 R2:

Video guide

Besides shrinking and extending partition, NIUBI Partition Editor helps move, copy, convert, defrag, wipe, hide, scan partition and much more.