Increase C drive space/size on Windows Server 2016

Updated on: November 16, 2019

This article introduces how to increase C drive space in Windows Server 2016, 3 ways to increase system C drive size for Server 2016 without losing data.

Low disk space of C drive is common issue in Windows Server 2016. It can't be better if you can increase C drive free space without wasting a long time to back up and restore everything. This article introduces 3 ways to increase C drive size on Windows 2016 server with Windows native tool and 3rd-party software. Follow the steps of corresponding method according to your own disk partition configuration.

Increase C drive space by merging partition D

This method is suggested only when there are no programs or Windows services installed in drive D, because this partition will be removed while merging with C drive.

To merge C and D drive, both Windows Disk Management and disk partition software can help you. But to increase C drive with Server 2016 Disk Management, your disk partition must meet the requirements below:

  1. There is another partition (D:) on the same disk.
  2. There are no programs or any Windows services installed in drive D, so you can delete it.
  3. There's another partition that has plenty of free space to save all files in drive D.
  4. Drive D must be a Primary partition. (The same with system C drive)

Steps to increase system C: drive space in Windows Server 2016 Disk Management:

  1. Transfer all files in drive D to other partition.
  2. Press Windows and X together on the keyboard and click Disk Management from the list.
  3. Right click drive D: and select Delete Volume, then its disk space will be converted to Unallocated.
  4. Right click C: drive and select Extend Volume, simply click Next till Finish in the pop-up Extend Volume Wizard windows.

With disk partition software such as NIUBI Partition Editor, there are no such limitations. Only several clicks are needed to merge C and D drive. Furthermore, all files in drive D will be moved to a new folder in C automatically.

To increase C drive disk space in Windows 2016 server, it is better to shrink other volume instead of merging, so you won't lose partition. Operating System, programs and anything else keep exactly the same with before without doing other operations.

Increase C drive size by shrinking D or other volume

To expand C drive by shrinking D or other volume, Windows Disk Management is useless, although there is built-in Shrink and Extend Volume functions, learn why.

While resizing partition in Server 2016, there is potential system and data damage risk, because all parameters of associated disk, partition and files must be modified correctly, files in some partition must be moved to new locations. Any slight error could cause system boot failure and/or data loss.

Better than other partition software, NIUBI Partition Editor has powerful technologies to protect system and data:

In most servers, there's free unused space in other volumes on the same disk. After shrinking these volume, part of unused space will be converted to Unallocated. After merging Unallocated space to C drive, it will be converted to part of unused space again.

How to increase C drive space from D in Windows Server 2016:

  1. Download NIUBI Partition Editor, right click D: drive and select "Resize/Move Volume", drag left border towards right in the pop-up window. (You may also enter an amount in the box of Unallocated space before)
  2. Right click C: drive and select Resize/Move Volume again, drag the right border towards the right side to combine Unallocated space.
  3. Click Apply on top left to execute. (Any operations before this step only work in virtual mode.)

If you want to increase C drive free space from non-adjacent E, there's an additional step to move partition D.

Video guide to increase C: drive size in Server 2016:

Video guide

Increase system C drive by cloning to other disk

In some servers, there's only single C drive in a disk, some servers have C and D on the same disk but both partitions are full. When there's no available free space in a physical disk, follow the steps in the video to expand C drive.

How to increase C (and D) drive space in Server 2016 by copying to larger disk:

Video guide

Increase C drive space in VMware/Hyper-V/RAID

If you want to increase C drive space in VMware/Hyper-V or RAID 0/1/5/10 array, there's no difference when there's free unused space on the same virtual disk, simply follow the steps in the first video above.

When all virtual partitions are full in hardware RAID arrays, first check if your controller has the ability to replace or add disk and rebuild array without losing data. If yes, additional space will be shown as Unallocated space on the end of original disk. Then follow the steps to move and combine Unallocated space. If no, you have to copy original RAID to a large physical disk or another raid array.

If the system disk is full in virtual machines, it's much easier, follow the steps to expand virtual disk in VMware or Hyper-V. Additional space will be also shown as Unallocated on the end after expanding original virtual disk.

In Summary

To increase C drive space/size in Windows Server 2016, native Disk Management can do little help. You'd better back up and run reliable partition software. As the safest tool, NIUBI Partition Editor helps accomplish this task well. It provides several ways to increase C drive free space in Server 2016 without losing data. It also helps do many other disk and partition management operations.