How to Clean Your C: Drive on Windows 10/11 (5 Methods)

To clean a full C: drive on Windows 10 or Windows 11, run Disk Cleanup with “Clean up system files” enabled to clear Windows Update leftovers, then turn on Storage Sense to handle temp files and Recycle Bin automatically. For deeper recovery, use HiBit Uninstaller’s Junk Files Cleaner and WizTree to identify the largest files on disk. Together these reclaim 5-50 GB on a typical clogged-up Windows install.

Applies to: Windows 10 (22H2) and Windows 11 (23H2, 24H2, 25H2) | Last updated: April 30, 2026

Key Takeaways

• Disk Cleanup’s “Clean up system files” mode is the single biggest win — it removes Windows Update leftovers, the previous Windows.old folder (up to 25 GB), and the WinSxS component cache. Built into Windows 10 and 11.
• Storage Sense (Settings > System > Storage) automates ongoing cleanup — temp files, Downloads folder, Recycle Bin. Set it once and forget about it.
• WizTree finds your largest files in seconds by reading the NTFS Master File Table directly — much faster than WinDirStat or TreeSize Free.
• HiBit Uninstaller’s Force Removal mode cleans up programs that conventional uninstallers leave behind, plus their leftover registry entries.
• Keep at least 15-20% of your C: drive free for normal Windows operation. Below 10% and you’ll see slowdowns; below 5% and Windows refuses to install updates.

Quick Steps

1. Open This PC > right-click C: > Properties > Disk Cleanup > Clean up system files. Tick everything except Recycle Bin (review that manually) and click OK.
2. Open Settings > System > Storage > turn on Storage Sense. Click “Configure Storage Sense” and set it to run weekly.
3. Download WizTree and run it as administrator. Sort by size to find the largest folders and files.
4. Open HiBit Uninstaller > Tools > Junk Files Cleaner. Run a scan and Clean.
5. In HiBit, sort installed programs by Size and uninstall what you don’t use. Use Force Removal for stubborn programs.

In This Guide

• Step 1: Disk Cleanup + System Files — Biggest one-shot space win.
• Step 2: Storage Sense — Automated ongoing cleanup.
• Step 3: WizTree to Find Large Files — Faster than WinDirStat.
• Step 4: HiBit Uninstaller for Junk Files and Programs — Deeper than Disk Cleanup.
• Step 5: Move User Folders to Another Drive — When you’ve still run out.
• Bonus: Remove Windows Bloatware with Winhance — Reclaim 1-3 GB of preinstalled apps.

Warning: Back up any important files before running cleanup tools. None of the steps in this guide should touch personal documents, but mistakes happen — a recent restore point is cheap insurance.

Step 1: Disk Cleanup with System Files

Disk Cleanup has been in Windows since XP and remains the fastest way to clear out megabytes of accumulated junk in one shot. The trick is the “Clean up system files” button — it’s the difference between freeing 200 MB and freeing 25 GB.

1. Open This PC, right-click your C: drive, choose Properties.
2. On the General tab, click Disk Cleanup.
3. When the first scan finishes, click Clean up system files. Disk Cleanup will rescan with elevated permissions.
4. Tick every category. Pay special attention to Windows Update Cleanup (often 4-8 GB) and Previous Windows installation(s) (up to 25 GB if you upgraded recently).
5. Click OK and confirm.

Tip: If you upgraded from Windows 10 to 11 within the last 10 days and might want to roll back, leave Previous Windows installation(s) unchecked. After 10 days Windows deletes it automatically anyway.

Step 2: Enable Storage Sense

Storage Sense is Disk Cleanup’s automated cousin. Once configured, it runs on a schedule and clears out the same junk without you ever touching it again.

1. Open Settings > System > Storage.
2. Toggle Storage Sense on, then click into it for full options.
3. Set Run Storage Sense to Every week.
4. Set Recycle Bin and Downloads to delete files older than 30 days. Skip this if you regularly leave installers or downloads in those folders.
5. Click Run Storage Sense now for an immediate first sweep.

Step 3: Find Large Files with WizTree

WizTree is a free disk-space analyser that reads the NTFS Master File Table directly. It scans a 1 TB drive in under 10 seconds — compared to several minutes for WinDirStat or TreeSize Free, which walk the file system normally.

1. Download WizTree from the official site (free for personal use).
2. Run as administrator (required to read the MFT).
3. Select your C: drive and click Scan.
4. Sort by Size descending. The biggest culprits are usually C:\Windows\Installer, the Steam library, hibernation file, virtual machines, and old Windows.old.
5. For files you want to keep but don’t need on C:, drag them to another drive. For pure junk (old ISOs, finished torrents, abandoned VMs), Shift+Delete.

Warning: Don’t delete files inside C:\Windows\Installer manually — those are the rollback caches Disk Cleanup handles safely. Touching them by hand can break uninstallers for installed programs.

Step 4: HiBit Uninstaller for Junk Files and Programs

HiBit Uninstaller is a free portable utility that goes deeper than Windows’ built-in tools in two specific ways: deeper junk-file scanning (browser caches, prefetch, log files Windows leaves behind), and Force Removal mode for programs whose uninstallers fail or leave leftover folders.

1. Download the portable HiBit Uninstaller and extract it.
2. Open Tools > Junk Files Cleaner, click Scan, then Clean. Repeat with Advanced Cleaner for browser caches and Windows logs.
3. On the main Uninstall screen, sort by Size. Right-click any program you don’t recognise or use and choose Uninstall (or Force Removal if the normal uninstaller fails).

Step 5: Move User Folders to Another Drive

If you have a second drive (a D: SSD, an external USB SSD, or a secondary HDD), you can move your Documents, Pictures, Videos, Music, and Desktop folders off the C: drive without breaking any apps. Windows tracks the new locations natively.

1. Create a folder on the destination drive (e.g., D:\Marco) with subfolders for Documents, Pictures, Videos, Music, Desktop.
2. Open File Explorer and navigate to C:\Users\<your username>.
3. Right-click Documents, choose Properties, switch to the Location tab.
4. Click Move, point it at D:\Marco\Documents, click OK. When asked, confirm Yes to move existing files.
5. Repeat for Pictures, Videos, Music, and Desktop.

This typically frees 20-100 GB on the C: drive depending on how much media you’ve accumulated. The shell folders still appear in Quick Access — they just live elsewhere physically. If you’d rather move installed programs too, that’s harder; the cleanest path is to uninstall and reinstall on the new drive, or use my guide on migrating Windows to a larger drive entirely.

Bonus: Remove Windows Bloatware with Winhance

Windows 10 and 11 ship with a layer of preinstalled apps you’ll never use — Xbox Game Bar, Microsoft Teams (consumer), LinkedIn, Solitaire Collection, OneDrive consumer, and so on. They’re typically 1-3 GB combined, and uninstalling them by hand from Settings takes 20+ clicks.

My own Winhance utility handles this in one screen — tick the bloatware categories you don’t want, click Apply, and Winhance uninstalls them and disables the related scheduled tasks so they don’t reinstall. It also includes a Software section to add back tools you actually use (Brave, VLC, 7-Zip) via WinGet.

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Frequently Asked Questions

How much free space should I keep on my C: drive?

Aim for 15-20% of the drive’s total capacity free for normal operation. SSDs need free space to handle wear leveling and cache, and Windows itself needs 8-10 GB free to install cumulative updates. Below 5% free, Windows refuses to install any updates at all.

Is it safe to delete Windows Update Cleanup files?

Yes — those are old cumulative-update payloads that have already been installed. Deleting them removes the option to uninstall a specific update, but Windows itself remains fully patched and stable.

Should I compress my C: drive to save space?

No. NTFS compression on the system drive saves 5-15% but adds CPU overhead on every read and write. The performance hit isn’t worth the small space gain on modern PCs — buy a bigger SSD or move user folders to another drive instead.

Can I move installed programs to another drive without reinstalling?

Settings > Apps > Installed apps in Windows 11 has a “Move” button for some Microsoft Store apps, but it doesn’t work for traditional desktop programs. For those, uninstall from C: and reinstall on the target drive — the program’s data and settings will reset unless you manually copy the AppData folder.

Will uninstalling Windows Store bloatware affect performance?

Yes, modestly. Each preinstalled app has scheduled tasks, background services, and notification handlers that consume small amounts of CPU and RAM. Removing 10-20 of them with Winhance reduces background activity noticeably on lower-end machines.