-firewallapi.dll -80204 Verified

If the error persists despite all fixes, core Windows networking stacks may be damaged. Use the to install the same Windows version over the current installation (keep files and apps). This replaces all system DLLs, including firewallapi.dll .

In an elevated PowerShell:

Start with the service check (Part 3, Step 1) – that resolves the issue for most home users. If you manage an enterprise network, include Group Policy audits and WFP restoration in your standard troubleshooting image. -firewallapi.dll -80204

Run as admin: fltmc filters Look for unusual filter drivers related to firewalls (e.g., wkflt, mfeavfk). Anomalies may require a clean boot. If the error persists despite all fixes, core