Fix Windows Security can't find antivirus error 0x8050800C

Quick answer

Open PowerShell as admin and run: Get-MpComputerStatus | fl AMServiceEnabled, AntivirusEnabled. If both show False, run Set-MpPreference -DisableRealtimeMonitoring $false then restart. Still broken? Move to the registry fix below.

Why you're seeing error 0x8050800C

Seen this one a lot. A client called last month after their kid's gaming PC started showing “Windows Security can't find an antivirus provider.” The kid had installed some “system optimizer” that nuked the Security Center's registry keys. Windows Security relies on the Windows Security Center service (wscsvc) to talk to antivirus providers — real ones like Defender, or third-party ones like Bitdefender. When those WMI or registry entries get corrupted, error 0x8050800C pops up.

It's not a real threat. Your system isn't necessarily infected. The Security Center just lost its phone number. Fixing it is straightforward, but you need admin access and patience.

Step-by-step fix

1. Check if Windows Defender is actually running

1. Open PowerShell as administrator (right-click Start, choose Windows PowerShell (Admin)).
2. Run: Get-MpComputerStatus | fl AMServiceEnabled, AntivirusEnabled, RealTimeProtectionEnabled
3. If all three show False, Defender is disabled or broken. Move to step 2.
4. If any show True, skip to the registry fix.

2. Re-enable Defender via Group Policy or Registry

Most common cause: a third-party antivirus left a “disable Defender” flag behind. Check this registry key:

HKLM\SOFTWARE\Policies\Microsoft\Windows Defender\DisableAntiSpyware

1. Press Win+R, type regedit, press Enter.
2. Navigate to that key.
3. If DisableAntiSpyware exists and is set to 1, double-click it and change to 0.
4. If the key doesn't exist, you're fine.
5. Restart your PC.

3. Repair WMI (Windows Management Instrumentation)

Had a client where a bad WMI query caused this error. Run these commands in admin PowerShell:

net stop winmgmt

winmgmt /resetrepository

net start winmgmt

If the reset fails, run: winmgmt /salvagerepository first, then retry.

4. Re-register Security Center DLLs

Open Command Prompt as admin (not PowerShell) and run these one at a time:

regsvr32 /s wscapi.dll

regsvr32 /s wscsvc.dll

regsvr32 /s wscproxystub.dll

Restart. Error should be gone.

Alternative fixes if the main approach fails

Third-party antivirus removal

If you had Norton, McAfee, or Avast installed previously, use their official removal tool. Their uninstallers often leave behind registry entries that confuse Windows Security. Run the tool from the vendor's site, reboot, then check error 0x8050800C again.

SFC and DISM scan

Corrupted system files can break Security Center. Run these in admin Command Prompt:

sfc /scannow

dism /online /cleanup-image /restorehealth

Restart after both finish.

Create a new local admin account

If nothing works, create a fresh admin account. Go to Settings > Accounts > Family & other users > Add someone else. Make it an admin. Log into that account and see if the error persists. If it doesn't, your main user profile is corrupted. Migrate your files and ditch the old profile.

Prevention tip

Stick with one antivirus. Running Defender alongside a third-party AV is fine in Windows 10/11 (Defender goes into passive mode), but don't keep switching. Each uninstall leaves junk. Also, never run those “registry cleaners” or “PC optimizers” — they break Security Center registry keys every time. I've cleaned up after three different clients who used CCleaner's registry cleaner and got this error. Just don't.

Keep Windows updated. Microsoft patches Security Center bugs regularly. If you're still on an old build like 1809, upgrade to 22H2 or later. That alone fixed the error for a client whose PC was stuck on 1909.