Why your friends can't join your ARK server (and how to fix it)

You did everything right. The server runs, you can join it from your own PC, and the moment a friend tries, nothing. The game sits there searching, or times out, or your server never shows up in their list at all.

This is the single most common wall in self-hosted ARK, and it’s usually not your fault. The good news is that it’s almost always one of a handful of causes, and you can test for each one in order until you find yours. This guide walks through them from most likely to least likely, with a plain-language test at every step. It applies to both ARK: Survival Ascended and ARK: Survival Evolved, and we’ll point out the few places they differ.

If you haven’t built your server yet and landed here early, our complete ASA hosting guide covers setup from scratch. This guide assumes the server exists and runs.

Three quick checks before the real diagnosis

These three cause a surprising share of “can’t join” reports, and they take a minute total.

1. The password. Server passwords are case-sensitive, and a password pasted from a chat message often brings an invisible space along with it. Have your friend type it by hand once, slowly. It feels too obvious to be it. Sometimes it’s it.

2. A version mismatch. When ARK releases a patch, your friends’ games update automatically, but your server doesn’t. An out-of-date server will refuse up-to-date players, usually with a vague timeout rather than a helpful message. If the game updated in the last day or two, update the server first (stop it, re-run your SteamCMD update command, start it again) and then have everyone retry.

3. The address itself. Your server has two different addresses, and mixing them up is the classic mistake. The one that starts with 192.168 or 10. is its address inside your house, and it only works from inside your house. Friends joining over the internet need your public address, which you can find by searching “what is my IP” on the server PC. And they need the port on the end, like 203.0.113.40:7777. Address without port, or house address instead of public address, both look exactly like a dead server from your friend’s side.

If all three check out, keep going. From here on we test methodically, starting close to the server and working outward.

Step 1: Prove the server works from inside your house

Before blaming the internet, confirm the server is actually reachable at all.

1. On the server PC, open Command Prompt and run ipconfig. Note the “IPv4 Address” (something like 192.168.1.50).
2. On a different computer in the same house, launch ARK.
3. Open the console (enable it in the settings if you haven’t, then press Tab) and type open 192.168.1.50:7777, using your address from step 1.

If you load into your world: the server itself is healthy. Your problem lives between your router and the internet. Skip to Step 2.

If you can’t join even from inside the house: the internet isn’t your problem yet, the server PC is. The usual cause is the Windows firewall. When the server first launched, Windows showed an “allow access” prompt, and if “Public” or “Private” was left unchecked, some connections get silently dropped. Open “Windows Defender Firewall with Advanced Security”, click “Inbound Rules”, and make sure there’s a rule allowing UDP port 7777 for both profiles. ASE also wants UDP 7778. Add the rule manually if it’s missing, then repeat the test.

Step 2: Test from outside your house without waiting on a friend

Debugging through a friend is slow, and their reports (“it just doesn’t work, man”) aren’t precise. You can simulate being a stranger on the internet yourself:

1. Take a laptop with ARK installed, or any second machine you can move.
2. Connect it to your phone’s mobile hotspot instead of your home wifi. It’s now “outside” your house as far as the internet is concerned.
3. In the console, type open YOUR-PUBLIC-IP:7777, using the public address from the quick checks above.

If that joins: your server is reachable from the internet, full stop. The problem is on your friend’s side: a typo in the address, an out-of-date game, or very occasionally their own network blocking outbound game traffic. Send them the address and port in writing and have them try the console method instead of the server list.

If that doesn’t join: something between the internet and your server is dropping the connection, and the next three steps find out what. A quick note before you reach for an online “port checker” website: most of them only test TCP, and ARK uses UDP, a different kind of traffic. Those sites will report your port “closed” even when everything is working, so don’t let one send you in circles.

Step 3: Check the port forward, the usual suspects

Port forwarding is the router setting that says “traffic on this port is expected, send it to the server PC.” When the hotspot test fails, the forward is the most likely culprit, and it fails in predictable ways:

• TCP instead of UDP. ARK traffic is UDP. A forward set to TCP, or left on “TCP only”, forwards nothing useful. “Both” is fine.
• The wrong ports. ASA needs UDP 7777 forwarded, plus UDP 27015 if you want the server appearing in the in-game list. ASE needs UDP 7777 and 7778, plus UDP 27015 for the list.
• The wrong destination. The forward points at the server PC’s house address, and that address can quietly change when the PC or router reboots. If your forward points at 192.168.1.50 but the PC woke up as 192.168.1.62, everything looks configured and nothing works. The fix is a “DHCP reservation” (sometimes “static lease”) in the router settings, which pins the PC to one address permanently. Set that first, then point the forward at it.
• The rule isn’t actually on. Some routers have an enable checkbox per rule, or need a save-and-apply, or want a reboot before new rules take effect. Toggle it off and on, apply, and if in doubt restart the router.

Fix anything that looks off, then repeat the hotspot test from Step 2. If it joins now, you’re done. Pass the public address and port to your friends and go play.

Step 4: Still stuck? Check for CGNAT

If the forward is provably correct and the hotspot test still fails, there’s a real chance the traffic never reaches your router at all, and no router setting can fix that.

Here’s the plain version. There aren’t enough internet addresses to go around anymore, so many internet providers stopped giving each home its own. Instead, one public address is shared across many households, a setup called CGNAT (carrier-grade NAT). It’s fine for browsing and gaming as a player, because your traffic goes out first. But it means unexpected traffic coming in, like a friend trying to join your server, has no way to find your specific house. Port forwarding can’t help, because the port on that shared address was never yours to forward.

How to check: log in to your router and find the internet or “WAN” address it reports. Compare it to what “what is my IP” says in a browser. If the two are different, you’re behind CGNAT. A router WAN address starting with 100. is also a strong giveaway.

If this is you, no amount of router fiddling will fix it, and you should skip straight to the options section below. If the two addresses match, one step left.

Step 5: The double-router problem (double NAT)

A lot of homes unknowingly run two routers: the modem-router combo box the internet provider supplied, plus a router you bought yourself. Each one has its own firewall, and forwarding a port on the inner one does nothing if the outer one is still dropping the traffic.

How to check: look at the WAN address your own router reports. If it starts with 192.168 or 10., your router is plugged into another router, not directly into the internet.

Three ways to fix it, best first:

1. Bridge mode. Log in to the provider’s box and look for “bridge mode” or “modem only” mode. That turns it into a plain modem and hands the public address to your own router, where your port forward already lives. Some providers do this from their app or a support call instead.
2. Forward on both. On the provider’s box, forward the same UDP ports to your router’s address. On your router, forward them to the server PC. Clunky, but it works.
3. DMZ your router. On the provider’s box, put your router’s address in the “DMZ” (a setting that passes all incoming traffic to one device). Broader than necessary, but your own router still firewalls everything behind it.

Then, one more time, the Step 2 hotspot test.

”My server doesn’t show up in the server list”

This one deserves its own section, because a server can be perfectly joinable and still not appear in ARK’s in-game browser. They’re separate systems: joining uses the game port, while the server list uses the query port (UDP 27015), which is a second port the server uses to advertise itself. If you never forwarded it, your server is invisible but healthy.

Two honest truths about the list even after you forward the query port:

• The unofficial server list is slow and crowded, in both ASA and ASE, and new servers can take a while to show up. Searching your exact session name helps. Patience helps more.
• The console is the dependable way in. open ADDRESS:7777 works regardless of what the list is doing. For ASE there’s also a nice trick: in Steam, open View, then Game Servers, then Favorites, and add YOUR-PUBLIC-IP:27015. Your server then appears in ARK’s Favorites tab with its proper name, and friends can join it there like a bookmark.

So if friends can join by address but nobody can find the server by name: forward UDP 27015, share the exact session name, and teach everyone the console command as the fallback.

If it’s CGNAT: your real options

Three ways forward, honestly compared:

• Call your internet provider and ask for a public IP address (sometimes sold as a “static IP”). Some providers will switch you for free, some charge a few dollars a month, and some won’t do it at all. Worth one phone call, because it makes the ordinary port forwarding route work again.
• Route your server’s traffic through a machine that does have a public address, using a tunnel or relay service. This genuinely works, and the manual versions are free or cheap. The trade is that you’re now setting up and maintaining one more piece of software, and it adds a hop your traffic travels through.
• Use a platform with the relay built in. That’s the next section, and this exact problem is the main reason it exists.

The same options apply if you can’t touch the router at all: dorm internet, an apartment building’s shared connection, or a household where someone else guards the admin password.

The way around all of it

Server Reforged turns a spare computer into a managed ARK server, and it sidesteps this entire guide by design. Your server connects outward to a relay we run, and your friends connect to that, so nothing ever has to find its way into your house. No port forwarding, no firewall rules, no router settings, and CGNAT simply doesn’t matter. Your friends can join no matter how your home internet is set up, and everything after setup is point-and-click from a dashboard. It’s free while we’re in beta, no credit card. The getting started guide shows the whole journey, or you can join the waitlist and we’ll email you when a spot opens up.

Quick answers

Why does my ARK server work on my network but not over the internet? Almost always one of four things, in order of likelihood: the port forward is wrong (wrong protocol, port, or destination), the Windows firewall is dropping traffic, you’re behind two routers, or your provider has you on CGNAT and incoming traffic can’t reach you at all. The steps above test for each in that order.

What ports does an ARK server need? ASA: UDP 7777 to join, plus UDP 27015 to appear in the server list. ASE: UDP 7777 and 7778 to join, plus UDP 27015 for the list. All UDP.

How do I know if I’m behind CGNAT? Compare the internet (WAN) address shown in your router’s admin page with what “what is my IP” reports in a browser. Different addresses means CGNAT. A router WAN address starting with 100. is also a giveaway.

My server is joinable by IP but not in the server list. Why? The list runs on the query port (UDP 27015), which is separate from the game port. Forward it and the server will advertise itself, though ARK’s unofficial list is slow enough that direct connect by address stays the reliable route.

An online port checker says my port is closed. Is the forward broken? Maybe not. Most port-checker websites only test TCP, and ARK uses UDP, so they report “closed” even on working setups. The phone-hotspot test in Step 2 is the trustworthy check.

Is there a way to skip all of this? Yes. A relay-based setup makes your server call out instead of requiring traffic in, which removes port forwarding and CGNAT from the picture entirely. That’s how Server Reforged works, and it’s free during the beta.