This is often the first place to look. It is the digital equivalent of realizing you can't leave your house because you've accidentally dead-bolted the door from the inside.
| Scenario | Fix | |----------|-----| | | Add Chrome to allowed apps in Windows Defender / firewall. | | Corporate proxy needed | Set correct proxy or use PAC file, authenticate. | | Extension causing block | Remove or whitelist site in extension settings. | | Electron / headless Chrome | Use --disable-features=BlockInsecurePrivateNetworkRequests . | | Localhost / 127.0.0.1 blocked | Run as Admin/root or use --allow-insecure-localhost flag. | | Windows UWP / WSL2 loopback | Run CheckNetIsolation LoopbackExempt -a -n=<appname> from elevated PowerShell. | err network access denied
Security software is the most common cause, as it can mistakenly flag your browser as a threat. This is often the first place to look
| Aspect | Detail | |--------|--------| | Error code | err network access denied | | Root cause | Policy or permission block (not timeout or DNS) | | Quick test | Disable extensions + check another browser + ping | | Most common fix | Add browser to firewall allow list | | Developer flag | --disable-features=BlockInsecurePrivateNetworkRequests | | | Corporate proxy needed | Set correct
Corrupted cache or problematic extensions can prevent pages from loading.