Extend Volume

Extend Volume on Windows Server 2012 R2

This article introduces how to extend volume on Windows Server 2012 (R2) with native Disk Management tool, if you cannot extend disk partition with it, run server partition editor software.

About Extend Volume functionality

The same with previous version, Windows Server 2012 provides built-in Extend Volume functionality in Disk Management tool, which can be used to expand both system partition and data volumes without losing data. In fact, Extend Volume is the GUI version of “Extend” command in DiskPart. Both native tools have serious restrictions that cause you unable to extend volume on Server 2012.

Extend Volume restrictions:

  • Only NTFS partition is supported, FAT32 and other types of partitions cannot be extended.
  • It can only extend the volume with adjacent Unallocated space on the right side.
  • Disk space in Logical partition cannot be extended to Primary partition, and vice versa.

In fact, another Shrink Volume functionality also has restriction: it can only shrink a volume towards left and produce Unallocated space on the right side. Thus, if you want to extend a volume by shrinking other one in Server 2012 Disk Management, it is impossible.

As you see, after shrinking drive D the 20GB Unallocated space is nonadjacent to C and on the left side of E, so Extend Volume is grayed out for both drive C and E.

Can't extend volume

How to run Extend Volume?

From the screenshot above, the 20GB Unallocated space can only be merged into drive D. If you want to extend C drive with Disk Management, the only option is by deleting drive D to get right adjacent Unallocated space.


  • Do not delete drive D if you installed programs or any Windows services are running from it, otherwise, the programs and services will stop working.
  • Remember to back up or transfer files before deleting a volume.
  • If D is a Logical partition, you still cannot extend C drive after deleting it.

However, if any drive fits for the requirements, Extend Volume can extend it easily.

Steps to extend volume with Windows Server 2012 Disk Management:

  1. Press Windows and R on your keyboard, type diskmgmt.msc and press Enter to open Disk Management.
  2. Right click the drive with right adjacent Unallocated space and select Extend Volume.
  3. Simply click Next till Finish on the “Extend Volume Wizard” window.

Extend Volume Wizard

Native Disk Management tool of Server 2012 can’t extend volume if you do not delete the right contiguous partition.

Extend volume with partition editor

With server disk partition software, it is much easier to shrink and extend volume, the most important aspect: no such restrictions.

Caution There is potential system damage and data loss risk when resizing disk partitions with 3rd party software, so remember to back up and use safe tool.

Better than other partitioning software, NIUBI Partition Editor provides unique 1 Second Rollback technology to ensure system and data intact. If any software or hardware issue occur, it automatically reverts the server to original status in a flash like nothing happened. Furthermore, it provides other Virtual Mode, Cancel-at-will and Hot-Resize technologies, as well as special File-moving algorithm to help resize partition much more safely and faster.

When resizing partitions on Windows Server 2012 (R2), NIUBI can:

  • Shrink a volume and produce Unallocated space on either side.
  • Combine contiguous Unallocated space on either side to extend volume.
  • Move partition and combine any non-adjacent Unallocated space.
  • Overcome the restriction of FAT32 partition and Logical/Primary partitions.
Download NIUBI Partition Editor, you’ll see all disk partitions on the right and available operations on the left side.


Detailed steps to extend volume on Windows Server 2012 with NIUBI:

Right click drive D and select “Resize/Move Volume”, drag the left border rightwards:

Shrink D rightwards

Unallocated space is generated on the left side of D.

Unallocated produced

Right click drive C and select “Resize/Move Volume” again, drag the right border rightwards:

Drag to extend

Unallocated space is merged into C: drive.

C drive extended

Right click drive D and select “Resize/Move Volume”, drag the right border leftwards:

Shrink D leftwards

Unallocated space is generated on the right side of D.

Unallocated generated

Right click drive E and select “Resize/Move Volume” again, drag the left border leftwards:

Drag to extend

Unallocated space is merged into E: drive.

Drive E extended

If you want to extend volume C by shrinking the non adjacent E, you need an additional step to move partition.

Watch the video how to shrink, move and extend volume on Server 2012 R2:

In Summary

Because of the inherent limitations, the built-in Disk Management can only help you extend partition in restricted condition. To extend volume on Windows Server 2012 (R2), 3rd party software is better choice. However, you’d better back up and use reliable tool. As the safest disk partition software, NIUBI Partition Editor helps you shrink, extend and move partitions easily and safely.

If you use any types of hardware RAID arrays, do not break the array or do any other operations in the RAID controller, simply follow the steps above.