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I am running a Minecraft server hosted at TCP 25565 which I can access via LAN, but cannot be reached externally.

I am not using any router and it is connected to an RG-Box Allied Telesis AT-iMG1525RF (my modem, which doesn't support port forwarding, all ports are opened) directly. I'm running vanilla 13w07a.

Windows Firewall is disabled as well as Avast!

I did a netstat -a search, and yes, I do have a connection listening at this port TCP.

Still, I get this "Connection timed out: Connect" error when trying to reach my server from anywhere outside of my network.

I called my ISP (who are fine with me having a server running and is mentioned in their terms of service) regarding this problem and they told me that they were only blocking port 24 and 25, all other ports is free to use. They also told me that I don't need to port-forward or anything, just plug my computer directly into the RG-Box, and I should be good to go. But I'm not.

It was working until three months ago. I can't change ISP as I live in an apartment where they decide my provider.

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What happened 3 months ago? Perhaps at that time the router got reset into a state that the ISP isn't expecting. – Ƭᴇcʜιᴇ007 Feb 24 '13 at 18:56
3 months ago we got a new router from the ISP. Exactly the same model, the old one just had some problems with overheating. But this problem is on hold atm. – Locercus Feb 25 '13 at 8:01

Now that you provided the model #, I searched for it and the first page reports it's a "Multiservice Gateway" not a modem including:

◾Stateful Inspection Firewall / NAT

You need to configure port-forwarding, NAT and/or a DMZ for that server. According to the documentation, it seems to be a customizable model targeted at ISPs to give to customers, so depending on what your ISP did to that gateway before giving it to you, you may not be allowed.

More info from Allied Telesis.

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How would I go around doing that, if it doesn't have a UI. Also, it's weird since my ISP wrote at their website, that I can just plug my computer to the "modem" and then I should be able to host a server. – Locercus Feb 23 '13 at 16:40
See my edit. :) – Ƭᴇcʜιᴇ007 Feb 23 '13 at 16:41

I gave them my external IP

That suggests the computer hosting a Minecraft server has a private/internal IP address, in which case a NAT device/service must be present to allow you to connect out to the Internet via your RG-Box.

Do you have multiple computers at your place all on the Internet? Even if not, please do command "ipconfig /all" on the machine hosting your Minecraft server and paste/comment the IP address (don't need subnets, gateways, or other entries).

Still, I get this "Connection timed out: Connect"

Timed out connections, if you're 100% sure you're handing out the correct IP address (I'm sure you are doing this right), tells me that there is either a firewall with no matching inbound connection acceptance rule dropping the connection attempt without response as to not expose your presence (known as a stealth port rather than a traditional closed port), or a NAT device/service has no configured port forwarding route so also drops the connection attempt.

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My modem doesn't have any UI, and thus nowhere for me to port forward. My ISP told me that all ports is open (except for 24 and 25). My internal ip is But I'm not sure why you'd want that. – Locercus Feb 23 '13 at 16:34
That internal IP will mean you have a NAT device/service sharing your external IP address. If you have no forwarding rules defined on it, then you won't be able to host a server. Do you not have a router in place? (possibly between your modem and computers) Also is your modem provided by your ISP? – Adambean Feb 23 '13 at 16:36
I do in fact have a router. But I rarely use it, as my computer is always wired up. I can connect my computer to the router instead and port forward that one, if you'd like? And yes, my modem is provided by my ISP. – Locercus Feb 23 '13 at 16:38
Your modem is in fact a router too if you're connected directly to it and have an internal IP address. It will have a NAT device built in that requires a port forwaring rule. Sounds like your ISP might not be letting you into your modem's interface intentionally. – Adambean Feb 23 '13 at 16:43
They told me that it didn't have an interface? – Locercus Feb 23 '13 at 16:46

If you can "surf the internet" from your server, and you can reach the server locally on its "real world IP" and you are not running a firewall, your ISP is blocking you - its that simple. I wonder if, when you called them and asked them about blocking if they were talking about outbound ports ? (Its not uncommon for ISP's to block port 25 outbound except to their mail server for spam mitigation reasons.)

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That's actually what they said. But this problem is on hold atm. Take a look at this, to get an idea of what I'm talking about:… – Locercus Feb 23 '13 at 19:26
up vote 0 down vote accepted

My ISP called me yesterday. They figured the reason where that they misread a 0 as an O when setting up the router with my MAC-ADRESS. They changed it, and the NAT firewall were removed. Thanks for your help everyone!

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