How to merge C and D drive partitions;

by Lance, Updated on: February 20, 2020

This article introduces how to merge C and D drive on Windows 10/8/7/Vista/XP & Server 2019/2016/2012/2008/2003, 2 ways to combine C and D drive without reinstalling Windows Operating System.

Applies to: Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, Windows Server 2019, Windows Server 2016, Windows Server 2012 (R2), Small Business Server 2011, Windows Server 2008 (R2) and Windows Server 2003 (R2).

Hard disk drive is an indispensable component for both Windows server and personal computer. To use the disk space more efficiently, you have to do many operations such as create, delete, format, resize, copy or convert partitions. Recently, many people ask me whether it's possible to merge C and D drive without reinstalling Windows and programs, because the system C drive is running out of space. The answer is yes, after merging D to C drive, there will be more free space in C drive again. In this article, I'll show you how to combine partition C and D without losing data.

How to merge C and D drive with Disk Management

In Disk Management console of Windows 10/8/7/Vista and Server 2019/2016/2012/2008, you can merge two drives by Extend Volume function indirectly. But for Windows XP or Server 2003, there is no such function, so you have to use third party partition editor software.

The GUI are absolutely the same in these Disk Management, so the steps below are valid for Windows 10/8/7/Vista and Server 2019/2016/2012/2008.

Steps to combine C and Drive together with Windows Disk Management:

  1. Back up or transfer all files in drive D to other place.
  2. Press Windows and R together on your keyboard, type diskmgmt.msc and press Enter to open Disk Management.
  3. Right click D: drive and select Delete Volume, then its disk space will be changed to Unallocated.
    Delete Volume
  4. Right click C: drive and select Extend Volume.
    Extend Volume
  5. Click Next in the pop-up Extend Volume Wizard window.
    Extend Volume Wizard
  6. The available disk space has been selected by default, simply click Next to continue.
  7. Confirm this operation and click Finish to proceed.

In a while, drive D is merged into C.

Partitions merged

If drive D is a Logical partition, the method above is invalid. Disk space of a Logical partition will be changed to Free after deleting, it can't be merged into Primary partition C with Extend Volume function in Disk Management.

How to combine C and D drive with free partition editor

It is much easier with 3rd-party software. To Windows 10/8/7/Vista/XP home computer users, there's free edition. Better than other software, NIUBI Partition Editor Free edition is 100% clean without any bundles. In addition, NIUBI has advanced 1-Second Rollback, Virtual Mode and Cancel-at-well technologies to protect system and data. With this free partition manager, all files in drive D will be moved to a folder in C automatically after merging.

Steps to merge C and D drive on Windows 10/8/7/Vista/XP and Server 2019/2016/2012/2008/2003:

  1. Download and install NIUBI Partition Editor, right click either C or D drive and select Merge Volume.
    Merge volume
  2. In the pop-up window, select both drive C and D, and then click OK.
    Combine C and D
  3. Press Apply button on top left to execute. (Otherwise, this operation only works in virtual mode).
    C and D combined

Resize partitions instead of merging them together

By merging D to C drive, there will be more free space in C drive again indeed, but there's an issue that D drive will be removed. If you installed programs to D drive, all these programs will stop working even though all files are moved to new locations.

It is suggested to resize partitions instead of merging them together. After shrinking D drive, part of free unused space will be changed to Unallocated and all files keep intact. Unallocated space can be combined to C drive easily. In this way, Operating System, programs and anything else keep the same with before. Follow the steps to expand C drive by shrinking D or other volume:

Video guide

Besides merging, shrinking and extending partitions, NIUBI Partition Editor helps do many other operations such as copy, convert, hide, wipe, defrag, scan bad sectors.