How to Fix CCleaner Not Working on Windows 11

CCleaner is one of the most popular PC optimization tools — known for cleaning junk files, managing startup programs, and improving performance. However, some Windows 11 users have reported issues where CCleaner stops working, won’t open, freezes during cleaning, or displays errors like “CCleaner has stopped responding” or “CCleaner won’t start”.

If CCleaner isn’t working properly on your Windows 11 PC, don’t worry — you’re not alone. In this guide, we’ll walk you through how to fix CCleaner not working on Windows 11, covering both quick fixes and deeper troubleshooting methods.

Why CCleaner May Stop Working on Windows 11

There are several reasons CCleaner might malfunction or fail to open:

Outdated CCleaner version incompatible with the latest Windows 11 build.
Conflicts with antivirus software or Windows Security.
Corrupted installation files or missing dependencies.
User permission issues or blocked registry access.
Damaged configuration or cache files in CCleaner.

Let’s go through the most effective ways to get CCleaner running again.

Step 1: Restart Your Computer

Before trying anything advanced, start simple. A system restart can clear temporary memory issues and background process conflicts that may stop CCleaner from launching.

Save your work and close all apps.
Click Start → Power → Restart.
Once your PC reboots, try launching CCleaner again.

If it still doesn’t open, move to the next step.

Step 2: Run CCleaner as Administrator

CCleaner needs elevated permissions to delete system junk and temporary files. Without admin rights, it may fail to run or display errors.

Right-click the CCleaner shortcut on your desktop.
Choose Run as administrator.
If prompted by User Account Control (UAC), click Yes.

💡 Tip: To make this permanent, right-click the shortcut → Properties → Compatibility tab → Check “Run this program as an administrator” → Apply → OK.

Now, try running the cleaning process again.

Step 3: Update CCleaner to the Latest Version

Older versions of CCleaner may not be fully compatible with newer Windows 11 builds. Updating ensures you have the latest compatibility fixes.

Open CCleaner (if it launches).
Click Options → About → Check for Updates.
Download and install the latest version.

If CCleaner won’t open at all, download the newest installer directly from CCleaner’s official website.

Avoid downloading from third-party sites — they may host outdated or unsafe versions.

Step 4: Disable Antivirus or Windows Defender Temporarily

Sometimes, antivirus software can block CCleaner’s processes, mistaking them for potential threats — especially when cleaning the registry or system files.

Temporarily turn off your antivirus software.
If you’re using Windows Security, do this:
- Press Windows + I → Privacy & security → Windows Security → Virus & threat protection.
- Click Manage settings under Virus & threat protection settings.
- Turn off Real-time protection temporarily.
Launch CCleaner again and see if it works.

If it opens successfully, add CCleaner to your antivirus exclusion list so it’s not blocked again.

Step 5: Reinstall CCleaner

If CCleaner files are corrupted, reinstalling a fresh copy can fix the problem.

Press Windows + I → Apps → Installed apps.
Search for CCleaner.
Click the three dots → Uninstall.
Restart your PC.
Go to CCleaner’s official site and download the latest version.
Install it and run it as administrator.

This should resolve most startup and freezing issues.

Step 6: Delete CCleaner Configuration Files

Sometimes CCleaner’s internal settings file gets corrupted, preventing it from launching properly. You can reset it by deleting the configuration file.

Press Windows + R, type: %appdata%\CCleaner and press Enter.
Delete all files in this folder (especially ccleaner.ini).
Restart CCleaner — it will create new default settings automatically.

Step 7: Check for Windows Compatibility Mode

If CCleaner isn’t opening or crashes on launch, running it in compatibility mode may help.

Right-click the CCleaner shortcut → Properties.
Go to the Compatibility tab.
Check Run this program in compatibility mode for: and select Windows 10.
Click Apply → OK.
Relaunch CCleaner.

This can fix version-specific issues caused by recent Windows 11 updates.

Step 8: Repair Windows System Files

If system components that CCleaner depends on (like .NET Framework or Visual C++ libraries) are corrupted, the app may stop working.

Open Command Prompt (Admin).
Run the following commands one by one: sfc /scannow DISM /Online /Cleanup-Image /RestoreHealth
Once both scans complete, restart your PC and try opening CCleaner again.

Step 9: Reset Windows Security (If CCleaner Is Blocked)

If Windows Security has flagged CCleaner as unsafe, you can unblock it manually.

Open Windows Security → Virus & threat protection → Protection history.
Look for any entries related to CCleaner.
Click the drop-down arrow and select Allow on device.

This ensures Windows Defender doesn’t quarantine or block CCleaner from running.

Step 10: Use the Portable Version of CCleaner

If the installed version still won’t run, try using the portable version (no installation required).

Download the CCleaner Portable ZIP from the official website.
Extract it to a folder (e.g., Desktop or Downloads).
Right-click CCleaner.exe → Run as administrator.

If the portable version works fine, the issue is likely with your installed version or registry entries.

Step 11: Check for Corrupt User Profile

If CCleaner launches fine in another account but not yours, your user profile might be corrupted.

Press Windows + I → Accounts → Other users.
Create a new local or Microsoft account.
Log in with the new account and install CCleaner.

If it works there, consider migrating your files to the new profile.

Step 12: Perform a Clean Boot

If a background app or service is interfering with CCleaner, performing a clean boot can identify it.

Press Windows + R, type: msconfig and press Enter.
Go to the Services tab → check Hide all Microsoft services → click Disable all.
Go to the Startup tab → click Open Task Manager → disable all startup items.
Restart your PC and try launching CCleaner.

If it works, re-enable services one by one to find the conflicting app.

Step 13: Check for Malware or System Infection

If CCleaner suddenly stopped working or you downloaded it from an unofficial source, malware could be the cause.

Open Windows Security → Virus & threat protection.
Click Quick scan or Full scan.
Remove any detected threats.

After the scan, reinstall CCleaner from the official website to ensure it’s clean.

Step 14: Update Windows 11

If your Windows build has bugs or security conflicts, updating it can help.

Press Windows + I → Windows Update.
Click Check for updates.
Install all pending updates and restart your PC.

Outdated system files or missing patches can cause app compatibility issues, including with CCleaner.

Wrapping Up

If CCleaner isn’t working on Windows 11, it usually comes down to permission issues, outdated software, antivirus interference, or corrupted files.

The most effective fixes are: