Microsoft Windows Apps are being blocked

Repair or reset each affected app first, then repair Windows components if all three apps still close immediately.

1. Repair and reset the affected apps

For Calculator and Notes—listed as Notepad or Sticky Notes, depending on the app installed:

1. Open Start → Settings → Apps → Installed apps.
2. Find the app and select the three-dot menu → Advanced options.
3. Select Terminate if shown, then Repair.
4. Launch the app and test it.
5. If it still fails, return to Advanced options and select Reset.

Resetting can delete that app’s locally stored settings or data. Microsoft documents Repair as the non-destructive first choice and Reset as the next step.^1^

For Windows Security, open Windows Terminal (Admin) or PowerShell (Admin) and run:

Get-AppxPackage Microsoft.SecHealthUI -AllUsers |
    Reset-AppxPackage

Restart Windows afterward. This is the accepted repair for the Windows 11 Security interface when it does not open.^2^

2. Update the apps and Windows

If multiple built-in apps are affected:

1. Open Microsoft Store → Library → Get updates.
2. Install all available app and Store updates.
3. Open Settings → Windows Update → Check for updates.
4. Install available regular updates and restart.

Microsoft’s Windows 11 Store-app guidance recommends updating Windows and Microsoft Store before reinstalling affected apps.^3^

If Calculator alone began failing immediately after installing a particular update, record its KB number under Settings → Windows Update → Update history. Do not remove an update merely because Calculator is affected; the available case-specific removal guidance applies only to the identified optional preview update KB5074828.^4^

3. Repair Windows system components

Because several Microsoft apps are failing, repair the Windows component store and protected system files:

1. Search for Command Prompt.
2. Select Run as administrator.
3. Run these commands in order:

DISM.exe /Online /Cleanup-image /Restorehealth
sfc /scannow

Allow DISM to finish before starting SFC, and do not close the window until SFC reaches 100%. Restart the PC and test the apps again. DISM supplies repair files, while SFC scans protected Windows files and replaces damaged copies.^5^

4. Reinstall individual Store apps

If Microsoft Store itself opens:

1. Go to Microsoft Store → Library.
2. Locate Calculator and the relevant Notes app.
3. Select Install or reinstall them if that option is available.^3^

Windows Security is a Windows component, so use its reset command and the component-repair steps rather than treating it like a normal removable Store app.

5. Least-destructive Windows repair fallback

If all affected apps still fail, reinstall the current Windows 11 version while preserving applications, files, and settings:

1. Keep the PC connected to power and the internet.
2. Open Settings → System → Recovery.
3. Under Fix problems using Windows Update, select Reinstall now.
4. Approve the prompts and restart when installation completes.

This reinstalls the same Windows version and repairs system files and components without removing existing apps, files, or settings.^6^

If that option is absent, it may be unavailable on a work/school-managed PC or on Windows 11 installations missing the required updates. Avoid downloading registry fixes or running Registry Editor as TrustedInstaller unless a Microsoft support engineer has identified the exact damaged registration; those changes are riskier and the reported cases address Windows Security alone, not simultaneous Calculator and Notes failures.

References

1. [Windows 11](https://support.microsoft.com/windows/apps/repair-apps-and-programs-in-windows#summary)
2. how to reset windows security which is not opening? - Microsoft Q&A
3. [Windows 11](https://support.microsoft.com/accounts-billing/fix-problems-with-apps-from-microsoft-store)
4. Calculator Not Working on Windows 11 After Update KB5074828 Jan 30, 2026 - Microsoft Q&A
5. Use the System File Checker tool to repair missing or corrupted system files | Microsoft Support
6. Fix issues by reinstalling the current version of Windows | Microsoft Support