Ok first off you'll need know your router's DHCP (Dynamic Host Configuration Protocol) range. To find this, you'll need to open a web browser, then enter your router's IP address in to the address bar, then hit enter.

NOTE: If you don't know your routers IP address you can find it by opening a command prompt on your pc, then type ipconfig, then hit enter. Look for the network adapter your currently using on the list. (E.g. Ethernet). Look for (Default Gateway). The numbers to the right are your router's IP address.

Ok enter your routers user name and password. If you don't have a username or password, you can use the defaults. You can search on the internet to find out this info for your make and model of router.

Once logged in, search through your router's settings until you see the section regarding DHCP. You should see an IP Address Range, and it usually starts with a pretty high number and ends with a higher number. So as long as you set your pc's static IP address to anything outside of the DHCP range, you should be good to go.

Now to set the static internal IP address. On the current version of Windows 10, go to Settings / Network & Internet, then select Change adapter options, Then right click the connection your currently on (like Ethernet for an example), Then select properties. Here you need to double click on (Internet Protocol Version 4 (TCP/IPv4)). Then you'll need to click on (Use the following IP address :). This is were you'll set your static IP address. You only need to change the last number, after the last dot in the IP address. (E.g. change 192.168.1.1 to 192.168.1.2).

On the (Subnet mask:) line, you shouldn't have to enter anything, just click on the area were you'd enter the numbers, and it should auto complete it.

On the (Default Gateway:) line, enter your routers IP address (the same one you entered in the web browser to log into your router).

On the (Preferred DNS server:) line, you can either use your ISP's (Internet service provider) Primary DNS, your router's IP address, or another Primary DNS like Google's. You can do some research on DNS servers if you want, because some DNS servers may give you better ping.

On the (Alternate DNS server:) line, you can either use your ISP's secondary DNS, or another secondary DNS like Google's.

Click ok.

Now when you open the command prompt and enter ipconfig, you should see your pc's new static IPv4 address.

Video explaining Internal and External IP addresses.
https://www.youtube.com/watch?v=EXXTFaTQSwU

Video about router DHCP range.
https://www.youtube.com/watch?v=i6Pmoygv-ZQ

Video on how to set a static Internal IP address.
https://www.youtube.com/watch?v=5iRp1Nug0PU

In the above image, you'll see an example of how to open up ports for Lost Planet.

Ok the first thing you should do is go to https://portforward.com/ and scroll down until you see List of all Routers. Click on that. Find your router's manufacturer on the list and click on it. Read what they have to say.

NOTE:They may not tell you to enter the static Internal IP address of the pc your on, but It only makes sense that you'll have to enter it somewhere. So If your router is like mine you'll need to enter your static IP address after every port or port range you want to open up, like in the picture above.

Anyway here are the ports. I got them straight from the Lost Planet Manual you can find on the Steam store page.

UDP 3075 send/receive
UDP 27215 send/receive
TCP 27030 to 27050 send
UDP 27000 to 27015 send
UDP 27216 send

NOTE: Your router may not have any option to select the send or receive part. Don't worry Mine didn't either.

In regards to UDP/TCP protocol. If your router has the option to set it to (Both), I'd play it safe and set it to what I have listed above.

Another thing worth mentioning is, that they had me enter the ports under my router's (Port Range Forwarding) section. It only makes sense because as you can see, some of the above ports, is actually a range of ports. E.g. 27030 to 27050. So your router will probably have a similar section.

Now to see if the above steps have worked, get on Lost Planet and create a match. I'd select "DEFAULT" under the "Connection Type" setting, for most cases, as I've heard that other "Connection Types", require all the players that want to see and join your match, have open ports as well.

Next, minimize the game window, and Look for the "View tab", in the upper left corner of the steam UI. Click on it and then select "Servers". Click on the "INTERNET" tab and you should see the match you created on Lost Planet, along with other information such as your user name, pop up on the list of servers. Also you can click on "CHANGE FILTERS" tab at the bottom of the window. Here you can create a filter to show only Lost Planet servers. You may need to click on the "QUICK REFRESH" or "REFRESH ALL" tab, to see your server pop up.

If you see your server pop up on the list, SUCCESS! Other players should be able to see and join, you match!

If it didn't work, or you're not sure you understand something in my Guide, feel free to leave a comment, and I'll do my best to help you out. Also you could call your router's manufacturer, or your ISP and tell them you need to open up some ports.

Also feel free to add me as a friend, If you want to play.