Extend partition server 2012

2 ways to extend partition in Windows Server 2012

To use disk space more efficiently and improve the server performance, it is better to create at least 2 volumes on the hard disk that is running Operating System. If you put everything into system C: drive, besides server performance down, it is difficult to locate the files that you need, in addition, C drive runs out of space very quickly. Actually, C drive becomes full sooner or later even if you create several volumes in this hard disk, because Windows Updates and many other kinds of files write into C drive continuously. This is the most common issue on both Windows PC and server.

To solve this problem faster and more easily, you can extend C drive without reinstalling Windows. Either Unallocated space or free space in other volumes can be added into C drive. To do this, Windows built-in Disk Management and third party software are optional choice. In this article, I’ll show you how to extend volume in Windows Server 2012 (R2) with these tools.

Extend partition server 2012

Extend partition with Disk Management

Disk Management is Windows built-in component that is activated by default. Besides the basic operations to create, delete and format partition, Server 2012 Disk Management has the ability to enlarge a drive with Extend Volume functionality. However, only when there is adjacent Unallocated space on the right side of a partition, you can extend this partition with Extend Volume. In most the server machines, there is no such Unallocated space, so 3rd-party software is needed in most cases.

Steps to extend partition in Windows Server 2012 Disk Management:

Step 1: Press Windows and R on keyboard, type diskmgmt.msc to open Disk Management.

Step 2: Right click the partition and select “Extend Volume“.

Extend C drive Server 2012

Step 3: Click Next in the Extend Volume Wizard window.

Extend Volume Wizard

Step 4: Available disk and space is selected by default, click Next to continue.

Select disk and space

Step 5: Click Finish to start extending.

Confirm extending

In a short time, this partition will be extended.

C drive extended

Besides Extend Volume, there is another Shrink Volume functionality in Disk Management, so some people try to shrink D and extend C drive, but failed. If you shrink D to get Unallocated space, when you right click C drive, you’ll find that Extend Volume is grayed out.

Extend Volume greyed out

As I explained above, to use Extend Volume, there must be adjacent Unallocated space on the right side. But after shrinking D, the Unallocated space is behind D rather than C, of course Extend Volume is disabled for C drive.

If you want to extend a data partition, you may consider transfer files, delete the adjacent volume to get Unallocated space and then extend this data partition with Extend Volume. But if you want to increase C drive space, do NOT delete drive D, otherwise, all services and applications that are running from it will stop working. The best choice is extending Server 2012 volumes with partition software.

Extend volume with partition software

There is no such limitation with partition software, and you just need to click and drag on the software. Example to extend volume on Windows Server 2012 with software:

Download NIUBI Partition Editor Server, right click the adjacent drive D and select Resize/Move Volume

Resize/Move Volume

In the pop-up window, drag left border rightwards to release free space from it.

Resize volume D

Click OK and back to the main window, where you’ll see that 20GB Unallocated space is generated behind C: drive. Right click C: drive and select Resize/Move Volume again.

Resize volume C

In the pop-up window, drag right border rightwards to combine the Unallocated space.

Extend C drive

C drive will be extended to 50GB. Click Apply button on top left to execute, done.C drive resized


  1. Different with Disk Management, NIUBI Partition Editor won’t carry out immediately, instead, it working in virtual mode, so you’ll see clearly how these partitions will be changed. Every operation you do will be listed as pending, and you can undo or redo before clicking Apply. Once you click Apply to confirm, this software will begin to change physical disk partitions.
  2. The pending operations with  can be done in Windows without rebooting, it is important to a server.

Thanks to the unique 1 Second Rollback technology and special file-moving algorithm of NIUBI Partition Editor, you can resize and extend partition on Windows 2012 Server safely and fast.