Solution when C drive is full in Windows 10/11/server

Most of Windows computer users encountered the problem that C: drive is getting full. This is annoying, because few people can solve this problem completely. Many people tried some methods after searching by Google, but system C drive becomes full again shortly. In this article, I’ll introduce how to fix C drive in Windows 11/10/8/7 and Server 2022/2019/2016/2012/2008 fast and easily.

Why C drive becomes full rapidly?

No matter you use Windows Server 2022/20192016/2012/2008/2003 or Windows 11/10/8/7, C drive is getting full sooner or later. Because there are large amount files saved or generated in this system partition. For example:

  1. Windows updates continuously save to C drive.
  2. Temp files and caches are save to C drive by default.
  3. All applications install to C drive by default.
  4. Some Games, Videos, Projects and other types of applications output large files in C drive by default, too.
  5. Some files still write to C drive even if you change installation path to other partition.
  6. Recycle Bin grows every day after you deleting files.
  7. Hibernation and System Restore service can eat up large amount of free space.

Symptom of C drive full

In both Windows PC and Server, when system C drive becomes full, you may receive “Low Disk Space” warning at bottom right corner – “You are running out of disk space on Local Disk (C:). To free space on this drive by deleting old or unnecessary files, click here.”

C drive full

When C drive is almost full in Windows 11/10/8/7 and Server 2008 – 2022, it will be changed to red in File Explorer. This design is also used to alert computer users.

C drive red

Whenever you see the Low Disk Space warning or C drive is showing red, you should try to solve this problem as fast as possible, because it causes many issue in this situation.

What happens if C drive is full?

  1. Computer/server performance down and system runs much slower.
  2. No space to install critical Windows updates.
  3. Computer/server stuck, reboot unexpectedly or even crash.

Solution of C drive is showing full in Windows PC/server

When system C drive is almost full in Windows server or personal computer, the first steps is cleaning up C: drive to reclaim disk space. If you cannot reclaim enough free space, move space to C drive from D or other partition. If there is not enough free space on system disk, clone disk to a larger one and extend C drive with extra disk space.

1. Clean up C: drive to reclaim space

There are more or less junk files in C drive, you can reclaim disk space after removing them. To accomplish task, the first choice is Windows built-in Disk Cleanup utility. It is safe, fast and easy to use.

How to clean up disk when system C: drive is full:

(Valid for Windows 11/10/8/7 and Server 2008/2012/2016/2019/2022)

  1. Open My Computer
  2. Right click C: drive and click Properties
  3. Click Disk Cleanup
  4. Select the files to remove in pop-up window.
  5. Conform the deletion.

To Windows Server 2008 and 2012, you need to install or enable Disk Cleanup in advance. Because it is not enabled by default in these Windows versions.

You may also use 3rd party software to accomplish this task, but the native Disk Cleanup tool is well enough. If you want to try more methods, follow the methods below:

2. Move free space and extend C drive

If you cannot get large amount of free space after cleaning up C drive, add more from other partition. With safe partition software, you can shrink other partition on the same disk and transfer to C drive. In this way, there will be more free space in C drive and everything keeps the same with before. Better than other tools, NIUBI Partition Editor has Virtual Mode, Cancel-at-well and 1-Second Rollback technology to protect your system and data.

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

Extend volume

Step 2: In the pop-up window, drag the left border rightwards to release free space on the left.

Shrink d drive

Drag to resize

Click OK and back to the main window, Unallocated space is made behind C: drive and a pending operation is listed on the left.

Volume shrank

Step 3: Right click C drive and select “Resize/Move Volume” again, in the pop-up window, drag the right border rightwards to merge this Unallocated space.

Extend C drive

Extend volume

Click OK and back to the main window, finally click Apply on top left to execute, done!

Volume extended

If there is not enough free space in D, you may get free space from other drive on the same disk.

3. Clone disk to a larger one

Besides C drive, if whole system disk is full, you can clone disk to a larger with the same program. It is easy to accomplish this task, follow the steps in the video to clone disk. Besides shrinking, extend partition and clone disk partition, NIUBI Partition Editor helps you do many other disk partition management operations.

Download to try