Extend C: drive partition in Windows 7

Updated on: November 16, 2019

This article introduces how to extend C drive partition in Windows 7 32/64 bit without losing data. 3 ways to extend C drive with Disk Management, diskpart cmd and NIUBI Partition Editor.

Windows 7 has been released for a long time and many users encountered the Low Disk Space problem - system C drive is running out of space and becomes almost full. It is common issue to Windows computers, because many kinds of files write into C drive continuously every day. This is the reason why many people want to resize partition and extend C drive in Windows 7. Nobody likes to waste a long time to reinstall Operating System and all programs.

Searching by Google and you'll find some similar questions such as:

  1. Is it safe to extend C drive, will it cause data loss?
  2. Which is the right tool for Windows 7 to repartition hard drive?
  3. How to increase C drive space step by step?

This article introduces 3 tools with detailed steps to resize partition and extend C drive in Windows 7 (32 & 64 bit).

How to extend C drive with Disk Management

Better than previous Windows XP, Windows 7 enhanced the ability of Disk Management by adding new Shrink and Extend Volume functions. This native tool helps change size of allocated partitions without losing data. However, because of many restrictions, it is not the best tool.

Steps to extend C drive partition with Windows 7 Disk Management:

  1. Press Windows and R together on the keyboard, press diskmgmt.msc and press Enter to open Disk Management.
  2. Right click the right contiguous partition D and select Delete Volume.
  3. Right click system C drive and select Extend Volume.
  4. Simply click Next till Finish in the pop-up Extend Volume Wizard window.

Do not delete drive D if you installed programs into it.

There is another Shrink Volume function in Disk Management that is able to decrease partition without losing data, why deleting drive D to expand C? This is because that Shrink Volume cannot generate required Unallocated space.

When you shrinking any partition (only NTFS is supported) with built-in Shrink Volume feature, Unallocated space can only be made on the right side. But Extend Volume can only extend Unallocated space to the left contiguous partition.

Unallocated space shrinking from D is non-adjacent to C drive and is on the left of drive E, therefore, Extend Volume is grayed out for both partitions.

If there is no or you cannot delete the right contiguous partition, Disk Management cannot help you expand C drive volume.

If the right contiguous partition (D or E) is Logical, you still cannot extend C drive even by deleting it.

Extend Volume disabled

How to extend C drive partition with diskpart

Unlike Disk Management that has graphical interface, DiskPart works via command prompt. Although the way to extend C drive in Windows 7 is different, Diskpart has the same limitations with Disk Management. That means, before extending C drive partition, you must delete the right contiguous one.

If you can delete the right adjacent partition and like to use command prompt tool, follow the steps to extend system C: drive with diskpart in Windows 7:

  1. Press Windows and R on the keyboard, press diskpart and press Enter.
  2. Type list volume in the diskpart command prompt window and press Enter, then you'll see all partitions but NO Unallocated space.
  3. Type select volume D and press Enter. (D is the right adjacent drive.)
  4. Type delete volume and press Enter.
  5. Type select volume C and press Enter.
  6. Type extend and press Enter.

To extend partition more easily and without so many limitations, 3rd-party partitioning software is better choice.

Diskpart extend

How to expand C drive with NIUBI Partition Editor

Comparing with Windows 7 native Disk Management and diskpart cmd, NIUBI Partition Editor has more advantages, for example:

If there is free unused space in any data volume on the same disk, you can transfer into C drive with NIUBI Partition Editor.

Download it, you'll see the main window with disk partition structure and other information. In my test computer, there are drive C, D, E and a system reserved partition in Disk 0.

NIUBI Partition Editor

Steps to extend C: drive partition in Windows 7 (32/64 bit) with NIUBI:

Step 1: right click drive D and select "Resize/Move Volume", in the pop-up window, drag left border towards right or enter an amount in Unallocated space before.

Shrink D

Then drive D is shrunk and Unallocated space is made on its left.

Partition D resized

Step 2: right click drive C and select "Resize/Move Volume", drag right border towards right in the pop-up window to combine the Unallocated space.

Extend C drive

Then the system partition C is extended from 40GB to 60GB.

Partition C resized

Step 3: click Apply on top left to execute. (All operations before this step only work in virtual mode.)

Watch the video guide how to extend C: drive in Windows 7 with free space in other partitions:

Video guide

No software can expand C drive with free space in another separated disk, if there is not enough free unused space on the same disk, follow the step to clone this disk to a larger one with NIUBI Partition Editor.

How to extend C drive volume in VMware/Hyper-V

If there is available free space on the same virtual disk, simply follow the steps above to shrink a data volume to get Unallocated space and then add into C drive.

If there is not enough free space in a disk, it is much easier if you use VMware or Hyper-V virtual machine. Firstly, follow the steps below to increase size of the virtual disk:

After that, additional space will be shown as Unallocated on the end of original virtual disk. Then follow steps above to extend C drive for Windows 7 virtual machine. Besides shrinking, moving, extending and copying disk partitions, NIUBI Partition Editor helps do many other operations.