Extend C drive

3 ways to extend C drive in Windows PC and Server

To Windows computer users, the most common and annoying computer issue is low disk space. Many people have the experience that C drive is running out of space and Low Disk Space alert pops up. Besides freeing up disk space, the most useful method is extending C drive with Unallocated space or free space in other drives. To extend C drive, there are 3 tools: DiskPart command prompt, Windows Disk Management and 3rd-party program. In this article, I’ll show you how to extend C drive in Windows 10/8/7/Vista/XP and Server 2016/2012/2008/2003 with these tools.

Extend C drive

Extend C drive with Disk Management

In Disk Management of Windows 10/8/7/Vista and Server 2016/2012/2008, there is built-in Extend Volume functionality, which can be used to extend C drive. However, there are some limitations and here I listed the precondition to extend C drive with Extend Volume in Disk Management:

  1. C drive should be NTFS. (FAT32 partition is not supported)
  2. In MBR disk, C drive should be Primary partition.
  3. There should be adjacent Unallocated space on the right side of C drive.

Meet these conditions and C drive can be extended easily, otherwise, Extend Volume is greyed out and disabled.

Extend Volume grayed out

Steps to extend C drive with Disk Management:

Step 1: Right click Windows on bottom left corner of the screen and select Disk Management:

Run Disk Management

Step 2: Right click C drive and select Extend Volume:

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

Step 5: Confirm and click Finish to proceed.

Confirm extending

In a while, C drive is extended.

C drive extended

Note: as I said above, meet the conditions and you can enlarge C drive, otherwise, you need partition software.

Expand C drive with DiskPart command

DiskPart is working from command prompt, which is more difficult comparing with GUI Disk Management. To extend C drive with DiskPart, you should meet the same 3 conditions, too. in addition, in Windows XP and Server 2003, you cannot extend C: drive via cmd from Windows, instead, you have to reboot and start from bootable disc. So DiskPart is the worst tool and it is not suggested. Here I just introduce the steps to the people who are interested with DiskPart.

Step 1: Insert your Windows XP or Server 2003 installation disc and boot into command mode.

Step 2: Type diskpart and press Enter

Diskpart command

Step 3: Type list volume and you’ll see all partitions but NO Unallocated space.

List volume

Step 4: Type select volume 1 to give focus to the system C: drive.

Select volume

Step 5: Type extend to proceed extending.

Extend volume

To resize volume and extend C drive in Windows, partition software is much faster and easier.

Enlarge C drive with free partition software

If you are running Windows 10, 8, 7, Vista or XP (both 32 & 64 bit), you may use free partition software to expand C drive.

No matter with Disk Management or DiskPart command, to extend C: drive should be adjacent Unallocated space on the right side. There is no such limitation with partition software.

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

Resize volume

In the pop-up window, drag left border rightwards to shrink D.

Shrink D

There is 20GB Unallocated space generated behind C drive.

Unallocated created

Step 2: Right click C drive and select “Resize/Move Volume” again. In the pop-up window, drag the right border rightwards to hold the Unallocated space.

Extend C drive

Step 3: Click OK, C drive is extended to 37.18GB by combining the 20GB Unallocated space. Click Apply on top left to execute, done.

C drive extended

What to do if there is not enough free space in the adjacent drive D? Simply resize other volume to get free space, only one addition step to move partition is needed. Watch the video:

In this article, I introduces 3 ways to extend C: drive in Windows PC and Server. As you see, Windows DiskPart command and GUI Disk Management have many limitations, they cannot help you in most conditions. The best choice is 3rd-party partition software.

Windows built-in tools have many limitations, but they are safe if you use correctly. 3rd-party programs are easier without limitations, but NOT every program is safe. All parameters of related disk, volume and files should be modified correctly while resizing and extending. If any software error or hardware issue such as power failure occur during this operation, these parameters may not be updated or modified incorrectly, of course you’ll lose data in this case.

NIUBI Partition Editor is integrated unique 1 Second Rollback technology which can ensure 100% system and data intact while re-partitioning. If any software or hardware issue occur, it can automatically roll back the computer/server to the status before resizing. In that case, nothing will be changed or damaged. So it is the first choice to resize and extend Windows partitions.