Free up disk space in Windows

A full drive slows Windows down, stops updates from installing and can crash apps. Windows has built-in tools to clean it up safely.

Symptoms

• A “Low disk space” warning.
• Drive C: shows red in File Explorer › This PC.
• Windows Update fails with error 0x80070070.

Cause

Temporary files, old update files, the Downloads folder and local copies of OneDrive files all grow over time.

Fix

1. Use Cleanup recommendations (Windows 11) or Temporary files

1. Open Settings › System › Storage.
2. Windows 11: select Cleanup recommendations and review each list.
3. Select Temporary files, tick Temporary files, Windows Update Cleanup, Delivery Optimization Files and Recycle Bin, then select Remove files.

Check the Downloads box only after you’ve moved anything you want to keep out of that folder.

2. Turn on Storage Sense

In Settings › System › Storage, turn on Storage Sense. It clears temporary files automatically and can make old OneDrive files online-only.

3. Free up space used by OneDrive

Right-click a large OneDrive folder in File Explorer and choose Free up space. The files stay in OneDrive and download again when you open them.

4. Find big files

In Settings › System › Storage, open Show more categories to see what’s using space. In File Explorer, search size:gigantic to find files over 4 GB.

If that didn’t work

• Uninstall apps you no longer use: Settings › Apps › Installed apps, sort by Size.
• Move videos and old projects to OneDrive, SharePoint or an approved external drive.

When to call us

• The drive fills up again within days. Something may be writing large logs or files.
• The PC has a small drive (128 GB or less). An upgrade is usually inexpensive.
• You’re unsure whether a large folder is safe to delete.