How To Resolve CCleaner Issues on Windows 11

Running CCleaner in Compatibility Mode on Windows 11

So, if you’ve been trying to run CCleaner on Windows 11 and noticed it’s acting all weird—like refusing to start or crashing randomly—you’re definitely not alone. It seems like this popular cleanup tool just isn’t fully tuned to play nice with the latest Win OS. Usually, running it as an admin, making sure it’s updated, or fiddling with permissions fixes most issues. But if those don’t work, here’s what finally got CCleaner working for me: running it in compatibility mode.

How I Got CCleaner to Launch in Compatibility Mode

Older programs like CCleaner have sometimes trouble with Windows 11’s newer architecture. Compatibility mode is basically Windows pretending it’s a bit older—like Windows 10 or even Windows 7—and usually that’s enough to get around weird launch issues or UI glitches. Here’s how I did it:

1. Find the CCleaner executable

   • Hit the Windows key + E to open File Explorer.
   • Type or paste into the address bar: C:\Program Files\CCleaner. If it’s not there, it might be in C:\Program Files (x86)\CCleaner.
   • Look for CCleaner64.exe. That’s the main file I used. On my older ASUS, it was buried in Advanced menu options, so don’t hesitate to dig around if you don’t see it immediately.

2. Open properties for CCleaner

   • Right-click CCleaner64.exe and choose Properties. Or, select it and press ALT + Enter.

3. Set compatibility mode

   • Switch to the Compatibility tab. Sometimes, it’s not obvious where it is—just click around, mine was kinda buried.
   • Check “Run this program in compatibility mode for:” and pick, say, Windows 10 or Windows 8 from the dropdown. The list usually includes several older Windows versions.
   • Also, to help it run smoothly, check Run this program as an administrator. Windows security can get picky about apps, especially older ones that might not be signed or fully compatible.

4. Apply and try launching

   • Click Apply>, then OK>. Sometimes, a quick restart of Windows Explorer (Ctrl + Shift + Esc, find Windows Explorer in the Processes tab, right-click > Restart) will help these changes take effect.
   • After that, just double-click CCleaner as usual or right-click and choose Run as administrator. For me, that last step was sometimes necessary if it still refused to open normally.

Why Compatibility Mode Made a Difference

Honestly, it’s kinda crazy how many older apps just choke on Windows 11—probably because they’re not built for the new architecture, or security is tighter now. Compatibility mode pretends your Windows is an older version—like Windows 10—so the app runs more like it’s expected to. It’s like, “Hey Windows, just pretend everything’s normal.” This really helped me fix launch snags and some UI glitchiness that came out of nowhere. Worth trying before throwing in the towel.

Extra Step: Whitelisting CCleaner in Windows Security

Sometimes, even after all that, Windows Defender or Security thinks CCleaner is suspicious because it’s an older app or unsigned. To prevent Windows from blocking it:

1. Open the start menu and type “Virus & threat protection,” then hit Enter.
2. In the window that opens, click on Manage settings.
3. Scroll down to Exclusions and select Add or remove exclusions.
4. Click Add an exclusion and choose File.
5. Paste the exact path to CCleaner64.exe. For me, it was C:\Program Files\CCleaner\CCleaner64.exe.
6. Double-click or hit Enter to add it. That should make Windows ignore CCleaner during scans, minimizing false alarms or accidental stops, especially if security is blocking it at a bad time.

This really helped in my case, because Windows Security sometimes gets overly cautious with older or unsigned apps, making troubleshooting more frustrating than it needs to be.

Why These Fixes Are a Big Deal

Overall, running CCleaner in compatibility mode and whitelisting it in security tools can be a total lifesaver. Windows 11’s security and compatibility layers are definitely more aggressive, and I’ve found that many apps just get caught up in the crossfire. It’s frustrating because it feels like older programs should still work fine, but alas, Windows doesn’t always cooperate out of the box. Still, these tweaks saved me a ton of hassle during a late-night troubleshooting session.

Hope this helped—was a total pain to figure out at first, but once I got the hang of compatibility modes and security exclusions, CCleaner finally started cooperating. Double-check your Windows version, make sure CCleaner’s updated, and verify the paths/permissions. Sometimes a reboot or running as admin really does make all the difference. Windows loves throwing curveballs, but with a bit of patience, it’s usually fixable. Good luck, and I swear—this might save someone else a weekend or two!