Iw4x Server — List

IW4x is a community-driven mod for Call of Duty: Modern Warfare 2 (2009) that replaces the standard matchmaking with a dedicated server browser. As of 2026, the master server and browser systems are managed primarily by the AlterWare community. IW4x Server List Overview

The server list is the heart of the IW4x experience, allowing players to choose specific game modes, maps, and community-run environments.

Master Server Transition: IW4x recently shifted from a "node system" to a centralized master server list to improve loading speeds and stability.

Server Discovery: When you launch the IW4x client, the in-game browser queries the AlterWare master server to populate the list.

Global Visibility: Public servers must comply with AlterWare hosting rules to appear in the browser; non-compliant or malicious servers are moved to a blacklist. Server Categories and Content

Community servers often differ significantly from the original 2009 experience:

Trickshotting: Dedicated servers like those featuring the SeshV2 menu are popular for high-skill cinematic kills.

Custom Content: Many servers include weapons and maps from later titles like Modern Warfare 3 or Black Ops. iw4x server list

Modified Rulesets: It is common to find "Sniper Only" or "High XP" servers, though some users report weapon nerfing in certain community-hosted environments. Technical Specifications for Hosters

For those looking to add a server to the list, the following requirements apply:

Software: Requires Visual C++ 2010 and 2015-2019 redistributables, along with the IW4x Dedicated Server files.

Hosting Limits: AlterWare restricts users to 10 servers per game and 25 total across their platform to prevent list spamming.

Configuration: Hosters must edit server.cfg to set the hostname, message of the day, and map rotation to distinguish their server in the list. Getting Started

To access the server list, you must first have the game properly installed:

Base Game: You must own a copy of Call of Duty: Modern Warfare 2 on Steam or the Microsoft Store. IW4x is a community-driven mod for Call of

Joining Friends: If a server isn't appearing in the list, players often use IP address connecting to bypass the browser.

💡 Note: Because IW4x relies on community-run projects like AlterWare, the availability of the server list can fluctuate based on maintenance or developer updates. I can provide more specific details if you tell me:

Are you trying to find a specific type of server to play on? Are you trying to host your own server?

Troubleshooting: "Server Authentication Error"

You found a server. You click join. It loads 70% and then kicks you back to the menu with a "Server Authentication Error."

The Fix: Your IW4x client files do not match the server's expected files. This usually happens if you installed custom skins or sounds. To fix:

1. Delete your main folder contents (backup your config).
2. Run the IW4x updater to restore vanilla files.
3. Try joining again.

Solution B: Enable UPnP or Port Forward

IW4x uses Peer-to-Peer connectivity. If you cannot see servers, your router might be blocking the master server handshake.

1. UPnP: Log into your router settings and enable UPnP (Universal Plug and Play).
2. Port Forwarding: If UPnP fails, forward port 28960 (UDP/TCP) to your PC's local IP address.

Modded Servers vs. Vanilla Servers

Scanning the IW4x server list, you will see two categories: Vanilla and Modded. Delete your main folder contents (backup your config)

• Vanilla: Standard MW2 rules. 6v6, perk system, killstreaks (Predator Missile, Harrier, AC-130). Best for purists.
• Modded (GSC mods): These change fundamental gameplay.
  • All or Nothing: One bullet, throwing knife, refill on kill.
  • Money Mod: Earn cash mid-game to buy weapons and perks.
  • Bot Warfare: Play against AI bots if the server is empty.

Look for the "Mod" column. If it says "None," it is vanilla. If it says "Bot_Mod" or "MW2Mod," expect chaos.

References

1. IW4x-Project. (2024). IW4x Client & Server Documentation. GitHub.
2. XLabs Team. (2022). Network Protocol Analysis for IW4x. Archived Wiki.
3. Activision. (2009). Call of Duty: Modern Warfare 2 – IWNet Technical Overview.
4. OpenIW4x Community. (2025). Master Server Status & Alternative Hosts. iw4x.gg/status.

Appendix A: Common Server List Filters (JSON query example)

  "gametype": "tdm",
  "map": "rust",
  "minPlayers": 6,
  "maxPing": 100,
  "mod": "BotWarfare"

Appendix B: Default IW4x Master Server List

• master.iw4x.gg:2086 (primary)
• master.iw4x.xyz:2086 (historical, may be offline)

This paper provides a complete reference for developers, players, and server administrators working with the IW4x server list.

Why Isn't My IW4x Server List Showing Anything? (Troubleshooting)

A blank IW4x server list is a common frustration. If you open the browser and see "0 servers," do not panic. Here is the fix:

What an “iw4x server list” is

An iw4x server list is a curated index of active iw4x multiplayer servers. It typically includes each server’s:

• Name and short description
• IP address (and optional port)
• Current map and game mode
• Player count / max players
• Ping / latency estimates
• Mod or rules notes (e.g., custom maps, weapon changes, banned mods)
• Connection instructions or required client versions

Server lists help players find servers that match their preferences (low ping, specific mods, certain player populations, or game modes like TDM, FFA, Gun Game).

2. Technical Architecture