How to run Windows 10 Diskpart cmd to extend volume C drive

Updated on: November 16, 2019

This article introduces how Windows 10 Diskpart extend volume command works, how to run DiskPart to expand C drive and other volumes, as well as its shortages.

What is Windows 10 diskpart command

DiskPart is a Windows built-in tool running from command prompt. You can do many disk and partition management operations such as create, delete, format, convert, shrink, extend volume, etc.

Press Windows and R on keyboard to launch Run, type diskpart and press Enter, then diskpart command prompt window will be open.

Input "?" and press Enter, you'll see all available commands.

Diskpart command

How to extend C drive with Windows 10 diskpart

Unlike Disk Management, Diskpart cmd lists all partitions without graphic configuration, so you won't know which partitions are in the same disk. Furthermore, Unallocated space won't be shown, but it is very important to extend a partition.

To better understand how diskpart extend command works, I suggest open the GUI Disk Management (Press Windows and X on keyboard).

Disk Management

From the screenshot:

  • I have 2 system reserved partitions and drive C:, D: and E: in Disk 0.
  • There is a 20GB Unallocated space between drive C and D.

Steps to extend C drive with Diskpart in Windows 10:

Step:1 In diskpart command prompt window, type list volume and press Enter.

List volume

Step:2 Type select volume 1 and press Enter.

Select volume

Step:3 Type extend and press Enter.

Extend volume

Diskpart reports successfully extended the volume. Check again in Disk Management, yes, C drive is extended from 30GB to 50GB.

Check in DM

How to extend partition D with Diskpart

All steps are the same with above except in step 2, type select volume 2 instead.

This time diskpart reports error "The size of the extent is less than the minimum."

Diskpart extend D

If I retry extending volume E, diskpart reports another error "The volume cannot be extended because the file system does not support it."

Diskpart extend E

Shortages of Windows 10 Diskpart cmd

Although the same with GUI Disk Management tool, Diskpart cmd has the ability to extend a partition, but in fact, most of hard drives can't be extended. If you want to extend volume with Windows 10 diskpart command, it is not a good idea, because this built-in tool has many shortages, including:

So, you'd better run professional partition software, which can help you shrink, move, extend and merge partitions. You just need to drag and drop on the disk map in graphical interface. Follow the detailed step to extend partition on Windows 10.