: After changing these settings, both you and the other user should restart your routers and Radmin VPN. 2. Firewall and Antivirus Exceptions
If the quick fixes failed, your router’s NAT (Network Address Translation) is too strict. You need + UPnP . radmin vpn relay tcp fix work
Ensure Radmin VPN and your game are added to the "Allowed Apps" list in Windows Firewall. Trust the Network: : After changing these settings, both you and
Windows often prioritizes your physical internet adapter over the Radmin virtual adapter, which can cause connection routing issues. Setting the metric to 1 forces Windows to prioritize the Radmin network for gaming traffic. Radmin Club Control Panel Network and Sharing Center Change adapter settings Right-click the Radmin VPN adapter and select Properties Internet Protocol Version 4 (TCP/IPv4) Properties "Automatic metric" in the "Interface metric" box. Restart Radmin VPN and your game. Radmin Club 2. Configure Firewall Exceptions You need + UPnP
| Step | Action | Success Indicator | | :--- | :--- | :--- | | 1 | Disable IPv6 on Radmin adapter | No more "IPv6 handshake failures" | | 2 | Add UDP 33640-33642 to Firewall | Windows stops blocking the handshake | | 3 | Port forward UDP 33640-33642 on router | Router stops blocking inbound UDP | | 4 | Disable antivirus "Web Shield" temporarily | Real-time HTTPS scanning kills VPNs | | 5 | Both users change DNS to Cloudflare (1.1.1.1) | Prevents ISP hijacking of VPN queries |
Switching your DNS to Google (8.8.8.8) or Cloudflare (1.1.1.1) can sometimes resolve persistent "Connecting" or relay states.