Hosting a Minecraft/Palworld/Valheim/CS2 server for friends usually ends the same way: you send the IP, they get "connection timed out", and everyone spends the evening in router menus. I built Server Doctor to shorten that. While building it I went through each game's docs and a lot of forum threads, and the same five causes keep coming up: Wrong protocol. Minecraft Java is TCP 25565, but Bedrock (19132), Palworld (8211), Valheim (2456-2457) and Rust (28015) are UDP. A TCP forward on a UDP game fails silently. CGNAT. If the WAN IP on your router's status page doesn't match "what is my IP" (or starts with 100.64-100.127), your ISP shares one public IP across many homes and port forwarding can't work at all. Testing from home. Joining your own public IP from inside your house often fails even when it's fine (no hairpin NAT). Test from a phone on mobile data. Wrong address. 192.168.x.x only works on your Wi-Fi. Version mismatch. Valheim and Palworld dedicated servers don't update themselves. What it does: you pick the game (15 so far, including Minecraft, CS2, Rust, Palworld, Valheim, ARK, Terraria, Project Zomboid and Satisfactory) and paste the address your friends use. It contacts the server once from the internet using that game's own protocol, adds a few optional answers (router WAN IP, what you forwarded, the error text) and ranks the likely causes with fix steps. It's a website and a Discord bot (/fix, /setup). Honest bits: - Free, no account. - No LLM at runtime: it's a rule engine plus a per-game knowledge base with sources. - Some games ignore test packets, so "no reply" there is a hint, not proof, and the result says so. - It only contacts the one public address you type and refuses private IPs. Try it: https://serverdoctor.app/fix Per-game guides: https://serverdoctor.app/help I made it, so I'd really like to hear where it gets your case wrong. Which game should be next?   submitted by   /u/Budget_Hornet [link]   [comments]