How to Add/Merge Unallocated Space to C Drive Server 2016

How to merge non adjacent unallocated space to a partition

Video Tutorial: shrink a volume, move partition, and add unallocated space to c drive


Want to better manage the disk partitions in Windows server 2016? Want to merge unallocated space to C drive? This article is about how to merge partitions to C drive without data loss with or without adjacent unallocated spaces.

Andrew Wright

Updated Feb 7, 2023

by Andrew Wright

Follow @IM-Magic

Why You Need to Merge Unallocated Space to C Drive

Having storage space problems on c-drive on Windows Server 2016? Well, Windows Server 2016 comes with a lot of upgrades, office-oriented tools, and advanced options, and when these amazing features start to get updates and expand their functionality, users suffer from an unusual low disk space problem. Unlike Windows 7, 8, 10, and Vista, Windows Server 2016 does not allow its users to allocate customized storage space to c-drive. Therefore, it comes difficult for system drive to occupy all necessary files.

If you are reading this article, you might have been trying to merge unallocated space to c-drive in Server 2016. But you failed, right? Well, follow this post and I will try to answer the reason as well as the solution to this problem.

Why I Cannot Merge Unallocated Space to C-drive Using Disk Management?

There are chances that you cannot merge or add unallocated space to c drive when the location of the c drive and the location of unallocated space matters.

  • C drive has adjacent unallocated space at right side (Successful with Disk Management)
  • C drive and unallocated space are not contiguous (Not successful, you need to delete the in-between partitions, or you may safely move the in-between partitions with 3rd party software to move the unallocated space close to c drive that can be extended when the two items are contiguous.)
  • No unallocated space on the disk (You may delete a volume in Disk Management, and delete the in-between volumes to get the unallocated space contiguous to c drive, or you may use Partition Resizer to shrink a large volume to produce unallocated space and then move inbetween volumes and then extend c drive with the unallocated spaces.)

Case#1 Expand c drive when it has contiguous unallocated space in Disk Management

Disk Management in Windows Server 2016 allows you to create, delete, format, and merge partitions depending upon certain conditions. If you have data partitions on the right side of c drive, you may backup data at first, and then delete it to be unallocated space and then add to c-drive, you can simply merge the unallocated space to c-drive. To merge unallocated space to c-drive using Disk Management, follow these steps:

  • Right click on c-drive and press “Extend”server 2012 to extend volume disk management
  • Enter the amount of unallocated present next to the c-drive and click next
  • Click on “Finish” to complete the setup

The unallocated space will be added to the c-drive right away when there is adjacent unallocated space to c drive.

These steps only apply if the unallocated space is present right next to the c-drive.

However, if there is another partition between the c-drive and unallocated, the Disk Management Utility cannot help you there until you delete the in-between drives.

Note:If you do not want to delete the in-between drives, you may use a third-party disk management software to merge unallocated space to c-drive.

Also read: extend volume greyed out server 2016 fixes

Add NONcontiguous Unallocated Space to c-drive Windows Server 2016

IM-Magic Partition resizer allows its users to shrink, extend, delete, format, create, and merge partitions with 100% data security and 0% involvement of OS or any other system files – your system is completely protected and there is no risk of data loss. Follow these steps to merge unallocated space to c drive using IM-Magic Server Edition.

download free windows 10 partition software

For example, when the disk volume maps like C, D, E, F when there is unallocated space right to E drive, how to move the free space to C?

move unallocated space

Solution: Move E drive right forward, the free unallocated space will be next to D drive; Move D drive right foward, the unallocated space will be moved to the C drive for extending.

Video - Move Unallocated Space Without Losing Files

Here are the steps.

  • Step 1 - Shrink a large volume, and then unallocated space will be created
  • Step 2 - Right click the inbetween drive, and move it, then the unallocated space will be moved to the right side of D drive
  • Step 3 - Right click D drive, go to option 'Resize/move Partition', and move the whole D drive right forward, and then the unallocated space will be next to the C drive to be claimed.
  • Step 4 - Right click C drive, go to 'Resize/move Partition', move the c drive border right to claim the whole free unallocated space
  • Step 5 - Click 'Apply' button in the last step to get every step applied (This is the last important step)

Also read: how to merge non-adjacent (nocotiguous) unallocated space to c drive

Related Product