Yes, ports are open, on the windows firewall as well as on the Fritz box I'm using. There's one thing left maybe: I'm using a Netgear router behind the Fritz Box, do I need to open the ports there as well?
Verify here; http://www.yougetsignal.com/tools/open-ports/ with your external ISP IP (default already filled in correctly if you are not using a proxy) and your LFS port (/port=) if it says " port open". It does only test TCP I think but thats the most important one for initial connection.
Could it relate to the adressed IP maybe? In the Windows Firewall it's 127.0.0.1, in the Fritz!Box configuration it's 192.168.178.25 and in the Netgear config it's 192.168.0.3 ... which is the right one?
You have an external IP, this one is provided by your internet provider, this is the outside door of your house of your complete network.
Fritz!Box is at the front door and processes all requests at the front door.
You have an internal door from the hall to the living room which is your Netgear router
It seems that your Netgear router has IP 192.168.178.25 (but I am not sure! Only you can find this out @Heimnetz overview) .. Fritz!Box needs to know this so the correct value is LFS port number + 192.168.178.25 @ Freigaben section. TCP and UDP needs to be active so two entries.
From that point the Netgear router takes over and redirect the request to your client machine: 192.168.0.3 so in your Netgear router it needs to have the port opened TCP&UDP LFS port to 192.168.0.3
If that all is correctly setup you can call on your front door with that website with your external IP + port. If it succeeds, connection probably also succeeds.
I made a mistake in the initial post. It needs to be the assigned IP by Fritz!box .. Probably 192.168.178.25 but in Heimnetz overview I think you can best figure out if it really is your Netgear router because it also mentions there on what LAN port the device is connected. Forget about the .1 blabla
*When you are really lost try cargame.nl Teamspeak chat (hostname, default port)... (or mic but I dont have headset activated now).
In the Windows Firewall: 192.168.1.1 (which is the Netgear's IP according to network overview)
In the Fritz!Box settings: the same
In the Netgear settings: 192.168.1.3 (the PC's IP address)
It still doesn't work ... hmmm ... What's the fault?
The funny thing is: The Fritz!Box keeps on telling me that the device establishing the internet connection has the 192.168.178.25 ... what does that mean?
Should be 192.168.178.25 .. If you are sure that is the Netgear router IP. I don't know if you are using Fritz!box Wifi and other LAN ports but otherwise your Netgear router is the only connected device and 192.168.178.25 sounds logical.
But I/we can not see what you do and have there (without screenshots).
What? In the main menu?
"Internet verbunden seit 22.01.2016, 11:44 Uhr, xxxxxxxxxx, IP-Adresse: "
It says 192.168.178.25 there? If it does then you are using your Netgear router for internet connection? Then it gets confusing. Why you have a Fritz!box then
Yes, I know. I have the same situation at my parents, Fritzbox with Wifi turned off and Asus router inbetween.. I modified my own Fritzbox myself like this guy who has made a webshop out of it; https://frixtender.de .. Its sort of OK.
That helps yeah... All router stuff seems to be setup correctly.
But the Windows firewall doesn't. Should say 127.0.0.1 as Lokale Adresse like Stock Car Extreme. Or "beliebig" to make it easy. With a dual NAT network setup like this, Windows Firewall is completely useless/overkill to begin with but ahhhh well..
Okay, I changed the entries in the Firewall to 127.0.0.1. The website for checking if the port is open still denies that, unfortunately. LFS server is open, though, but I guess nobody will still be able to join ...
I have the same.. You could theoretically choose a different entry port and convert it to another one internally but to not make things very complicated its best to keep same port numbers as configured @LFS.
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By the way... When you are bored update your Netgear firmware; http://kb.netgear.com/app/answers/detail/a_id/27488/related/1 .. Improves Wifi stability and boot time. Actually that was done @update 58 but 60 is the latest. You have update 30.
Ah well, let's call it a day and see what tomorrow brings. Thank you very much for your time and support so far! Much appreciated!
UPDATE: Not so well. After investigating a bit I found out that port forwarding is simply not possible according to my internet/cable provider (which is Unitymedia btw.). The reason is IPv6 and DS-lite. Hosting a server here seems to be possible only with having a business rate ...