Common Multiplayer Issues and Solutions
UPnP
This is a technology that allows an application (like Grim Dawn) to communicate with your router. If your router supports UPnP (most do), Grim Dawn can tell your router to allow other people to connect to your computer when you are hosting a game.
Why is this needed? Routers by default are designed to BLOCK anyone connecting to your computer. This is a security thing. You don’t want random/malicious computers connecting to your computer unless you explicitly allow it.
Ports
A port is designated by a number. In the case of Grim Dawn this number is 27016. Think of this as a phone number. As we mentioned above, a router by default is configured to say, “I’m sorry, that number is unreachable”, to anyone who tries to call you on any number. So if nothing was configured, you would host your Grim Dawn game, the game would tell Steam that you have a game ready, Steam would call you up on 27016 and your router would tell Steam, “I’m sorry, that number is unreachable”, and no game would be shown as available to anyone else.
Forgotten Gods: Steam/GoG Crossplay
With the release of the Forgotten Gods Expansion (patch v1.1.0.0) Steam/GoG crossplay has been enabled. Servers require additional ports to be forwarded, either by enabling UPnP (automatic) or manually via your router’s port forwarding setup.
When setting up manual port forwarding, the following ports must be forwarded to your servers internal IP address.
42805
42852-42872 (all ports in this range)
If UPnP is enabled in game, these additional ports should be automatically forwarded.
In an ideal world, what should happen?
If everything works in the most typical case, this is what happens…
You host a Grim Dawn game.
The game attempts to talk to your router via UPnP.
If your router supports UPnP, it tells Grim Dawn that it does. Grim Dawn then tells your router that it should “open” port 27016 and when anyone tries to connect to that port it should redirect the call to your computer.
Grim Dawn then starts up and tells Steam that you have a game running. Steam connects to you on port 27016, your router perks up and redirects that connection to your computer running Grim Dawn. Grim Dawn sees the connection from Steam and tells Steam what it needs to know.
Other people contact Steam looking for games to join. Steam tells them about all the games it knows about including yours. A person now sees your game and opts to connect to it. Steam tells them where your machine/router is and that person calls you up on port 27016. Your router passes the connection onto your computer, Grim Dawn receives the connection, and the player is allowed to join.
So, why didn’t this work for you?
Unfortunately, there are lots of reasons why you might be having problems. Here are some of the more common problems:
Firewall/Anti-Virus Software: This is often a cause of problems. Like we mentioned above, a router is designed by default to not let people connect to your computer. Firewall software is software that runs on your computer and does the same thing - blocks people from connecting to your computer. So even if UPnP worked and successfully told your router to direct connections on port 27016 to your computer, any firewall software running on your machine might then just block the connection right at your computer.
Your router doesn’t support UPnP: Though most routers do support UPnP, some don’t. And the reality is, many routers say they do support UPnP, but actually don’t - or not that well.
You’re behind more than one router: Usually your Internet provider will provide you with a router. It’s the box you either plug your computer into or connect to via WiFi. If you have another router between you and that, you won’t be able to host a Grim Dawn game. Keep in mind that cable modems these days are typically both a modem and a router, so any other router between you and your cable modem may actually be a second router.
What can you do to work around these issues?
Disable firewall software: Usually firewall software can be configured to work well with applications like Grim Dawn, but while you’re trying to diagnose your problem, it’s best to disable it as completely as possible. Once things are working, try turning it back on again. You may have to configure it to allow network traffic in and out on port 27016. Keep in mind that some anti-virus software have firewalls built in, so also disable that when you’re trying to get things to work. For specific instructions on how to disable this type of software, identify what you have and search online for brand specific instructions.
Check Grim Dawn’s network diagnostics: Go to Options -> Network from Grim Dawn’s main menu. Make sure “UPnP Status” says “Available” and make sure that “Enable UPnP” is checked. Now click the “Test” button. This will give you some information in the right panel. It will try to identify if you are behind more than one router as well.
Open port 27016 on your router manually: If you’ve done all these steps and/or your router doesn’t support UPnP, you’ll most likely have to open or “Port Forward” port 27016 manually. In order to do this, you’ll use your normal web browser to connect to your router, log in, and configure your router to forward port 27016 to the computer you are running Grim Dawn on. Again, you will be doing this through your browser, not Windows control panel, network settings, or anything like that. In order to do this you will need to collect some information:
- The IP address of your router. This is a 4 part number that looks like “192.168.1.1”. Your number most likely will be different. This is also usually known as your “gateway address”.
- The IP address of your computer. This is a similar looking address. In most cases, your computer’s address will only differ in the last (4th) part of the number. So if your router’s IP address is 192.168.1.1 your computer might be something like 192.168.1.20.
- Note: You can get both IP addresses by running “ipconfig” from a command prompt on your computer. See the video link below for an example.
- The administrator username and password for your router. If you never changed it, it’s probably still the factory default. It might be something like “admin” for the username and “password” for the password. These will vary greatly from router to router, so check your router’s manual if you have it or search online for “default router admin password” and the manufacturer and model of your router. If you or somebody else has changed the password you may have to hard-reset your router to reset it to the factory default. Again, see your manual or search for that online.
Once you have this information, you will navigate to your router by putting the router’s IP address into your browser where you normally would type an address. You may have to add “http://” to it first.
So, as an example you might type in “http://192.168.1.1” (minus the quotes) into your browser and hit enter. If all goes well, you should be prompted for a username and password. This is the username and password of your router like we talked about above.
If you have the right username and password, you can log in. You should then be presented with a web page that allows you to configure your router. Look for “Port Forwarding” or something similar. The exact behavior of this will vary from router to router, so refer to your manual or search online for specific instructions.
Assuming you have made it this far and have discovered where to set up port forwarding on your router. You will typically be asked for what port to forward - in our case it’s 27016, what protocols to forward - in our case we would like to port forward both UDP and TCP, and to what address we want to forward to - this is the IP address of your computer where you will be running Grim Dawn.
Here is a video of a guy manually setting up port forwarding on his router:
Watch the video to generally see how it’s done. Keep in mind the specifics will be different for different routers.
At this point things should work. Simple right?