Windows Update failed with error 0x8024402C — cannot connect to update server
Windows Update encountered an unknown error. (0x8024402C)
Windows Update failed to connect to its update server — either Windows Update on the internet or a corporate WSUS server — with error 0x8024402C (WU_E_PT_WINHTTP_NAME_NOT_RESOLVED). This is a network connectivity error meaning the Windows Update client could not resolve or reach the update endpoint.
Windows Update encountered an unknown error. (0x8024402C)
Why it happens
The device has no internet connectivity or DNS resolution is failing for Windows Update endpoints.
A proxy server is configured but is not allowing access to Windows Update URLs, or the proxy configuration in Windows is incorrect.
In an enterprise environment, the WSUS server URL configured in Group Policy is incorrect, the server is offline, or the client cannot reach the WSUS server.
Firewall or network security appliance rules are blocking connections to `windowsupdate.microsoft.com` or `update.microsoft.com`.
The Windows Update service is configured to use a proxy that is no longer available.
How to fix it
Verify internet connectivity and DNS resolution: open Command Prompt and run `ping windowsupdate.microsoft.com`. If this fails, resolve the connectivity issue first.
Check and correct proxy settings: `netsh winhttp show proxy`. If a proxy is configured that should not be, reset it with `netsh winhttp reset proxy`.
Run the Windows Update troubleshooter: Settings > Update & Security > Troubleshoot > Windows Update.
In an enterprise/WSUS environment: check Group Policy (gpedit.msc or gpresult /h gpreport.html) under Computer Configuration > Administrative Templates > Windows Components > Windows Update for the configured WSUS server URL. Verify the WSUS server is reachable from the client.
Flush DNS cache and reset network components: `ipconfig /flushdns`, `netsh winsock reset`, `netsh int ip reset`, then restart.
Check that the Windows Firewall and any network security policies allow outbound HTTPS (port 443) to Microsoft Update endpoints. Required URLs are listed in Microsoft's documentation for Windows Update firewall requirements.
