My Windows 11 laptop has a small size C drive. It only has 80GB in space. Now, only 6GB free space is available and the computer starts lagging these days. Now, Windows 11 keeps warning me about low disk space. I'm not very experienced with system stuff, so I'm worried about deleting the wrong files and breaking something important.Because C drive is almost full, I've already cleaned up some obvious big files like old downloads and emptied the Recycle Bin, but it didn't free up much space. Not sure if it's safe to delete things like temporary files, Windows update files, or old system folders.Could someone explain what's safe to delete on the C drive and what I should absolutely avoid touching?

You'll get most of the space back by deleting "Windows update files" and "Temporary Files" from your system. Run "Disk Cleanup" on your PC and select the C drive too see how much space you can free up. Hope that helps!

Cleaning up a C drive can be a daunting task if C drive is full, but I'm here to guide you through it safely. Before we begin, let's emphasize the importance of being cautious: deleting the wrong files can indeed cause problems, so we'll take a step-by-step approach.What to do if C drive is full：1. Delete temporary files if C drive is full:Press the Windows key + R to open the Run dialog box.Type %temp% and press Enter to open the Temp folder.Delete any files and subfolders in the Temp folder.2. Delete Windows update files:Open File Explorer and navigate to the Windows Update folder (C:\Windows\SoftwareDistribution\Download).Delete any files in the Download folder.Be cautious not to delete files in the SoftwareDistribution folder.3. Delete old system folders:Open File Explorer and navigate to the C drive.Look for old system folders, such as System Volume Information, Windows.old, or other folders with old dates.Be cautious not to delete folders containing essential files, such as Windows, Program Files, or Users.4. Check the Disk Cleanup tool:Press the Windows key + R to open the Run dialog box.Type cleanmgr and press Enter to open the Disk Cleanup tool.Follow the on-screen instructions to delete unnecessary files and system files.

If your C drive is full, here are some steps to help you free up space:Check for updates: Ensure your Windows is up-to-date, as newer versions often include features to help manage disk space.Empty the Recycle Bin: This might sound obvious, but it's easy to overlook. Make sure to empty the Recycle Bin regularly.Reinstall Windows: If none of the above steps help, you might want to consider reinstalling Windows. This will give you a clean slate and free up space on your C drive.Extend the C drive: If you have another drive on your computer, you can extend the C drive by using the disk management tool. Before you start deleting:Backup your data: Once your C drive is full, then deleting unnecessary data is inevitable. Ensure that you have a recent backup of your important files and documents. You can use an external hard drive, cloud storage (e.g., OneDrive, Google Drive), or a backup software.Identify essential files: Make a list of the files and folders you need to keep, such as:Documents, videos, and photosInstalled programs and their foldersWindows system files and folders (e.g., Windows, Program Files, Users)Backup files and folders

NirCmd is a small command-line utility that allows you to perform various system tasks easily. If your C drive is full, you can use NirCmd to free up space by deleting unnecessary files, clearing temporary files, or managing system resources.Here are some ways you can use NirCmd if C drive is Full:1. Delete Specific Large Files or FoldersYou can delete specific files or folders you no longer need, for example:nircmd deletefile "C:\Path\to\file\or\folder\*"Note: Be very careful with delete commands to avoid deleting important system files.2. Automate Cleanup TasksYou can create scripts that run cleanup commands automatically to free space regularly.3. Clear Recycle BinEmptying the Recycle Bin can free significant space:nircmd emptybin

Use build in Storage Sense in settings. It shows you where you have big files and automatically clean unnecessary windows files.https://support.microsoft.com/en-us/windows/manage-drive-space-with-storage-sense-654f6ada-7bfc-45e5-966b-e24aded96ad5

C drive is full. What should I delete to clean up C drive safely?

12 Replies

Indiaer
Silver Contributor
Dec 30, 2025
Cleaning up a C drive can be a daunting task if C drive is full, but I'm here to guide you through it safely. Before we begin, let's emphasize the importance of being cautious: deleting the wrong files can indeed cause problems, so we'll take a step-by-step approach.
What to do if C drive is full：
1. Delete temporary files if C drive is full:
Press the Windows key + R to open the Run dialog box.
Type %temp% and press Enter to open the Temp folder.
Delete any files and subfolders in the Temp folder.
2. Delete Windows update files:
Open File Explorer and navigate to the Windows Update folder (C:\Windows\SoftwareDistribution\Download).
Delete any files in the Download folder.
Be cautious not to delete files in the SoftwareDistribution folder.
3. Delete old system folders:
Open File Explorer and navigate to the C drive.
Look for old system folders, such as System Volume Information, Windows.old, or other folders with old dates.
Be cautious not to delete folders containing essential files, such as Windows, Program Files, or Users.
4. Check the Disk Cleanup tool:
Press the Windows key + R to open the Run dialog box.
Type cleanmgr and press Enter to open the Disk Cleanup tool.
Follow the on-screen instructions to delete unnecessary files and system files.

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C drive is full. What should I delete to clean up C drive safely?