C drive full Windows 7

Solution of C drive is full in Windows 7

It is very common that system C drive getting full in Windows 7 both 32 and 64 bit. This issue is annoying, because many people do not know why and what to do. Some people succeeded reusing disk space but C drive becomes full again in a short time. In this article I’ll introduce the complete solution to fix Windows 7 C drive full issue.

If C drive is running out of space and becomes full, when you open File Explorer or My Computer, C drive will be shown as red instead of default blue. Furthermore, Windows pops up an alert of ‘Low Disk Spacefrom the right side of your Windows taskbar with warning message: ‘You are running very low on disk space on OS (C:), To free space on this drive by deleting old or unnecessary files, click here‘.

Low Disk Space

Both design are used to alert computer user about the dangerous situation. When system partition C is full, you’ll suffer from computer performance down. Your Windows 7 system runs much slower, stuck, reboot unexpectedly or even crash. Thus, you’d better fix this issue as fast as possible.

Why C drive is running out of space

There could be many reasons, but the most common reasons include:

1. C drive shows full but it is not

It is a possible reason, but few people have such experience. Only one of my readers feedback such issue caused by virus, try to scan your disk with antivirus software if you think the disk space shows incorrectly.

2. C drive shows full but many folders seem empty

Many people feedback such experience: they try to check the files and folders in C drive and found many ’empty’ folders that occupied much disk space. In this situation, change the folder option to show hidden files.

In any folder of Windows Explorer, click Organize on top left corner and then click Folder and search options:
Folder option

Switch to View tab, select ‘Show hidden files, folders, and drives’.
Show hidden files

3. C drive is filling up with files

This is the most common reason why C drive is getting full in Windows 7. Windows Updates, 3rd-party programs and many other types of files write into C drive every day, of course it runs out of space sooner or later, no matter how big it is.

How to fix C drive full issue

To solve this problem, you’d better complete 3 steps below, otherwise, you may encounter this problem again in near future.

Steps to fix C drive full issue in Windows 7:

Step 1 Increase C drive space

All disk partitions are created while installing Operating System or by OEM manufacturers, but you can change partition size with partition software without reinstalling. As long as there is free space in any other drives, you can transfer into C drive, so there will be plenty of free space in C drive. This step is very important to the computers that C drive are created small.

Caution There is potential system and data damage risk while resize disk partition, so you’d better back up and use safe partition software.

Better than other commercial and free disk partition software, NIUBI Partition Editor provide 1 Second Rollback, Virtual Mode and Cancel-at-will technologies to ensure system and data intact.

Download NIUBI Partition Editor Free Edition and follow the step in the video to expand C drive.

Step 2 Reclaim disk space

In system C drive, there are many unnecessary files that can be deleted safely such as temporary files, cache, files in Recycle Bin. You can reclaim disk space by deleting these files. To to this, you may either use 3rd-party optimization software or Windows 7 Disk Cleanup utility. I always suggest Windows native Disk Cleanup, because it is safe, fast and able to clear up many types of unnecessary files.

How to clean up to reclaim disk space:

  1. Right click C drive and click Properties:Free up space
  2. Click Disk CleanupWindows 7 Disk Cleanup
  3. Select the files you want to delete and click OK to proceed.Select files
  4. Clean up system files in the same window. To get more free space, you may switch to More Options tab, where you can clean up installed programs and System Restore points.Clean up space

To the computer that never free up disk space, you may get over 10GB free space in C drive.

 Change the way running your computer

After above 2 steps, you can solve Windows 7 C drive full issue, but I still suggest you consider the options below:

  1. Install new programs to another separate partition such as D.
  2. Change the default file output location to other large partitions, especially for the program for pictures, videos, games, projects, etc.
  3. If the hard disk is small and you cannot get enough free space from other partitions, consider cloning to a larger disk.
  4. Run Windows 7 Disk Cleanup once a month to delete new generated junk files.


When C drive is getting full in Windows 7, expand it as large as possible and run Disk Cleanup to reclaim disk space regularly.