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Software Conspiracy

Network Errors

VPN not connecting on Windows 11 — How to fix

Most VPN-not-connecting issues on Windows 11 trace to: broken WAN Miniport drivers, Windows network stack out of sync, or the VPN client itself needing reinstall.

Time
20 min
Difficulty
medium
Applies to
Windows 11, Windows 10
Updated
May 25, 2026

Symptoms

  • Built-in Windows VPN connects then immediately disconnects
  • Third-party client (OpenVPN, WireGuard, NordVPN, ExpressVPN) connects but no traffic flows
  • Error 720, 800 or 809 returned

Likely causes

  • WAN Miniport drivers corrupted
  • VPN client adapter not bound to TCP/IP
  • Windows Firewall blocking the VPN protocol
  • MTU too high for the VPN tunnel

How to fix it — step by step

  1. 01

    Reinstall the VPN client

    Most VPN clients (OpenVPN, WireGuard, NordVPN, ExpressVPN, ProtonVPN) include a Repair option. Use it first.

  2. 02

    Reset network

    Settings → Network & internet → Advanced network settings → Network reset.

  3. 03

    Recreate WAN Miniport drivers

    Open Device Manager → View → Show hidden devices → expand Network adapters. Uninstall every WAN Miniport entry, then reboot — Windows reinstalls them clean.

  4. 04

    Lower MTU on the VPN adapter

    Most VPN tunnels need MTU 1400 or lower.

    netsh interface ipv4 set subinterface "VPN" mtu=1400 store=persistent
  5. 05

    Check Windows Firewall

    Windows Security → Firewall & network protection → Allow an app through firewall. Confirm your VPN client is allowed on both Private and Public networks.

Frequently Asked Questions

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