How to shrink C drive in Windows Server 2016?

When installing Windows Server 2016, if you forget to edit partition, all disk space will be used by C: drive. It is bad idea to keep single C drive and save everything into it. You’d better create several partitions to save different types of files. To do this, you can shrink C drive to get Unallocated space.

To shrink partition C in Windows Server 2016, you may use either Windows built-in utility or 3rd-party software. Windows built-in Disk Management has “Shrink Volume” function to decrease partition size. However, it cannot shrink C drive in some cases. In this article, I’ll introduce how to shrink C drive in Windows Server 2016 with Disk Management and safe partition software.

Shrink C drive in Server 2016 Disk Management

Step 1: Right click Windows on bottom left and then click Disk Management.

Open disk management

Step 2: Right click C: drive and select Shrink Volume.

Shrink volume

Step 3: Enter the amount of space and click “Shrink” button.

Type amount

In general, C drive will be shrunk in a short time.

C drive shrank

Why cannot shrink C drive with Server 2016 Disk Management

There are 3 common reasons why Disk Management cannot shrink C drive in Windows Server 2016:

  1. File system error – in that case, the available free space is 0 in shrinking window.
  2. Unmovable files – Disk Management cannot shrink volume to the point where “unmovable” files are located. These files include Paging page, hibernation and other large files.
  3. Available free space conflict – if you don’t enter an amount in the shrinking window, maximum available free space will be used by default. If you entered a larger amount or the available free space is reduced a lot before clicking “Shrink” button, you’ll receive error message.

Shrink C drive with safe partition software

To shrink system C drive in Windows Server 2016, third party software is more powerful. But because of there’s potential system/partition damage risk, you’d better back up in advance and run safe software. Better than other tools, NIUBI Partition Editor has 1-Second Rollback, Virtual Mode and Cancel-at-well technology to protect system and data.

When shrinking C drive in Windows 2016 server, this program has “Optimize File System” feature to fix error. It can move these “unmovable” files, so you can shrink a partition to minimum size with it. To shrink and extend partition with NIUBI, you just need to drag and drop on the disk map.

How to shrink C drive volume in Windows Server 2016 without losing data:

Step 1: Download NIUBI Partition Editor, right click C: drive and select “Resize/Move Volume“.

Shrink c

Step 2: In the pop-up window, drag either left or right border to the other side. If you drag right border leftwards, Unallocated space will be made on the right side.

Drag to shrink

Drag to shrink

Step 3: Press Apply on top left to execute.

C drive shrank

Options after shrinking C: drive

1. Create new volume

Step 1: Right click the Unallocated space, and select “Create Volume“.

Step 2: Click OK to use entire Unallocated space and all default settings, or do advanced operations:

  1. Add label (name) to the new volume.
  2. Select a drive letter
  3. Select file system
  4. Select cluster size
  5. If the hard disk is MBR, you can select create new volume as Logical or Primary here.
  6. Drag either border or input a value to specify partition size and location.

Create volume

2. Extend other drives

If you want to shrink C drive to extend other volume such as D, make Unallocated space on the right when shrinking partition C. Then right click D: and select “Resize/Move Volume“. In the pop up window, drag left border leftwards to combine this Unallocated space.

Drag to extend


Extend D

Click OK and back to the main window, click Apply on top left to execute.

D extended

Follow the steps to decrease C drive and extend system reserved partition in Server 2016. Besides shrinking and extending partition, NIUBI Partition Editor helps you do many other disk partition management operations in Windows Server 2003/2008/2012/2016/2019/2022.

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