Shrink volume

How to shrink volume C in Windows 10?

When installing Windows 10 to a new hard disk, if you forgot to create volumes, all disk space will be used by C drive except the small reserved partitions. As we know, it is not a good idea to use such big C drive and put everything into it. Instead, you’d better create separate volumes for applications and data. Is there a way to decrease C drive space without reinstalling? Yes, in this article I’ll introduce how to shrink volume in Windows 10 without losing data.

Shrink c drive

Shrink volume in Windows 10 Disk Management

In Windows 10 Disk Management, you can shrink volume without 3rd-party software. Microsoft added advanced Shrink Volume function from Windows Vista, which can be use to decrease size of a volume easily.

Steps to shrink C drive with Windows 10 DM:

  1. Right click Windows on bottom left corner and select Disk Management.
  2. Right click C drive and select Shrink VolumeShrink volume
  3. Enter the amount of space to shrink, click Shrink to execute.Enter space

In a short time, C drive will be shrank.

C drive shrank

Cannot shrink C drive in some situation

If you want to shrink C drive to smaller size to release more free space, you may get error message, for example: I use the default space to shrink, to Windows 10, it is the maximum available space can be shrank.

Shrink volume

After clicking Shrink, I got the error message: “There is not enough space available on the disk(s) to complete this operation.”

Error message

Checking the log in Event Viewer, Event 257 shows: “The volume (C:) was not optimized because an error was encountered: This shrink size specified is too big. (0x89000021)

Error log

Have you noticed the tip when enter the amount of space to shrink: “You cannot shrink a volume beyond the point where any unmovable files are located. See the “defrag” event in the Application log for detailed information about the operation when it has completed.”

For example: C drive is made up of 4 blocks A, B, C and D. If the unmovable files are located in block C, you cannot shrink volume to block B or A even though there is free space.

C drive block

This is the reason why I got error message when using the default maximum space. Then what is the “unmovable” file? Page file and the very large file such as hibernation, system backup files. If there are many types of these files in C drive, you can only shrink a little space.

Then is there a way to get out of this trouble? Yes, use third party professional partition software.

Shrink volume with partition software

As the most popular disk partition management software, NIUBI Partition Editor helps you shrink C drive in Windows 10 much more easily, and you just need click and drag to shrink Windows 10 volumes.

Comparing to Windows Disk Management, NIUBI Partition Editor has many advantages:

  • Both NTFS and FAT32 partitions can be shrank.
  • Unallocated space can be generated on either side.
  • It can move the “unmovable” files, so it can shrink volume to minimum size.

How to shrink partition in Windows 10 with NIUBI:

Download NIUBI Partition Editor and you’ll see the main window.

NIUBI main window

Right click the drive that you want to shrink (here is D) and select Resize/Move Volume. Drag either border towards to other side.

If you drag the left border rightwards

Shrink D drive

Unallocated space will be generated on the left side of D

Shrink to left

If you drag the right border leftwards, Unallocated space will be generated on the right side of D.

Shrink to right

Note: this software work in virtual mode to avoid mistake, to shrink physical disk partition, click Apply on top left to execute.

In Summary

To shrink partition in Windows 10, you may try the build-in Disk Management tool, but it cannot shrink volume in some situations. For example: except NTFS partition, FAT32 and other types of partitions are not supported by Shrink Volume. It can only generate Unallocated space on the right side. Furthermore, you can only shrink little space if there are some unmovable files. To shrink volume in Windows 10, NIUBI Partition Editor is better choice. Besides shrinking and extending disk drive, it can do many other operations.

Download to try