How to Fix Low Disk Space on C: Drive Out of Nowhere

🔧Step-by-Step Fixes

Fix 1: Use Windows Storage Sense

The built-in Storage tool shows exactly where your space went:

1. Press Windows + I to open Settings
2. Go to System > Storage
3. You'll see a breakdown of what's using space on your C: drive
4. Click Temporary files
5. Check all the boxes including "Downloads", "Recycle Bin", "Previous Windows installations", and "Windows Update Cleanup"
6. Click Remove files
7. This can free up several gigabytes immediately

Go back to Storage and click each category to see what's taking up the most space.

Fix 2: Run Disk Cleanup (Deep Clean)

Disk Cleanup can remove files Storage Sense might miss:

1. Press Windows + S, type disk cleanup, and open it
2. Select your C: drive and click OK
3. Click Clean up system files button
4. Wait for it to scan again
5. Check all boxes, especially "Previous Windows installations", "Windows Update Cleanup", and "Temporary Windows installation files"
6. Click OK and confirm

The "Previous Windows installations" folder alone can take up 20GB or more.

Fix 3: Find and Delete Large Files

Use Windows tools to locate the biggest space wasters:

1. Download a free tool like WinDirStat or TreeSize Free
2. Run it and select your C: drive
3. It will scan and show you a visual map of what's taking up space
4. Look for unexpectedly large folders
5. Common culprits: C:\Users\[YourName]\AppData\Local\Temp (temporary files), C:\Windows\Temp (Windows temp files), game installation folders, video editing projects
6. Delete or move large files you don't need

Be careful not to delete system files - stick to your personal folders and known programs.

Fix 4: Clear Microsoft Store Cache

The Store cache can grow surprisingly large:

1. Press Windows + R to open Run
2. Type wsreset.exe and press Enter
3. A blank command window will appear for about 10 seconds, then the Microsoft Store opens
4. The cache is now cleared

Fix 5: Move Files to Another Drive

If you have another drive (D:, external drive, etc.), move files there:

1. Press Windows + I to open Settings
2. Go to System > Storage
3. Click Advanced storage settings
4. Click Where new content is saved
5. Change the save locations for Documents, Music, Pictures, Videos, and new apps to another drive if available
6. Click Apply

Then manually move existing files from your Documents, Pictures, etc. folders to the new drive.

Fix 6: Uninstall Unused Programs and Games

Programs can take up more space than you realize:

1. Press Windows + I to open Settings
2. Go to Apps > Installed apps
3. Click Sort by: Size to see the largest programs first
4. Look for games, programs, or apps you no longer use
5. Click the three dots and select Uninstall
6. Games can easily be 50-100GB each

Fix 7: Disable Hibernation (If You Don't Use It)

Hibernation creates a file as large as your RAM:

1. Press Windows + X and select Terminal (Admin)
2. Type powercfg /h off and press Enter
3. This deletes hiberfil.sys which can be 8-16GB or more
4. Only do this if you never use hibernate mode (different from sleep)

Fix 8: Adjust System Restore Space

System Restore can use a lot of space for restore points:

1. Press Windows + S, type create a restore point, and open it
2. Click your C: drive, then click Configure
3. Move the Max Usage slider to a lower percentage (5% is usually enough)
4. Click Apply and OK
5. This doesn't disable System Restore but limits how much space it can use

Fix 9: Check for WinSxS Folder Bloat

The Windows component store can grow very large:

1. Press Windows + X and select Terminal (Admin)
2. Type DISM /Online /Cleanup-Image /AnalyzeComponentStore and press Enter
3. This shows if cleanup is recommended
4. If yes, type DISM /Online /Cleanup-Image /StartComponentCleanup and press Enter
5. Wait for completion (can take 15-30 minutes)