UPnP not working well

[thany]

I'm running µTorrent 1.6.1 on XP-SP2 with the firewall disabled. No other firewall has been installed, so firewall can't be the problem. UPnP is enabled and working on my NAT-router, proven by the fact that other applications using UPnP work just fine (Miranda IM, for example). If it helps to track down the problem, my router is a SpeedTouch 546i version 5.4.0.11.

I'd like to help by giving more information, but µTorrent doesn't seem to reveal the HTTP-requests/responses that makes up the UPnP-functionality...

[Ultima]

Try enabling verbose logging in the Logger tab -- does it show anything about an XML file when UPnP errors out?

[thany]

Unfortunately, even with verbose logging, I can't get it to reveal more than just this:

"Unable to map UPnP Port."

...which of course is pretty useless for a developer to track down the problem

[Switeck]

Although it seems off-topic, can you get µTorrent unfirewalled by port forwarding your router?

If not, then it may even be your modem's handling of UPnP that's the problem. It may work for some UPnP apps, but not others.

[thany]

Of course if I forward the port to the PC it works perfectly... but it kinda defeats the purpose of UPnP. Also, my PC's get IP-adresses through DHCP, so that too will have to stop.

What if I use Wireshark to see what's going on between µTorrent and the router, would that help?

[Switeck]

It might confirm if the router is seeing and obeying the UPnP request.

But my guess is something ELSE is causing the firewalled condition.

[thany]

You *might* be right, all I see happening is this:

M-SEARCH * HTTP/1.1\r\n

Request Method: M-SEARCH

Request URI: *

Request Version: HTTP/1.1

HOST: 239.255.255.250:1900\r\n

ST:upnp:rootdevice\r\n

MAN:"ssdp:discover"\r\n

MX:3\r\n

\r\n

And then nothing. 5 seconds or so after this the log says "Unable to map UPnP Port." as if the router doesn't even respond. Maybe my router only listens on TCP/2869, while the above request was made on UDP/1900 (the other UPnP port). But I can't be sure...

Why does µTorrent stick with just UDP/1900 anyway, instead of trying both ports before erroring out?

In any case, what do you recommend on further examining this problem?

[DreadWingKnight]

Sounds like the router is ignoring the UPnP request entirely. Not much we can do about that.

[thany]

Alright, so now I have another router

It's the Netgear FWG114P and UPnP is proven to be working. It shows one UPnP-mapping at port 1325 for Miranda IM, so this proves UPnP does work... Yet µTorrent continues to show "Unable to map UPnP Port".

[Switeck]

Does the latest µTorrent v1.7 beta exhibit the same UPnP problem?

[thany]

I looks that way, but 1.7 does provide more info:

[01:43:36]  UPnP: Discovered new device: http://192.168.10.2:80/upnp/service/WANIPConnection
[01:43:36]  UPnP: ERROR -3 mapping port 6881 -> 192.168.10.21:6881; Deleting Mapping and trying again
[01:43:36]  UPnP: ERROR -3 removing port 6881
[01:43:36]  UPnP: ERROR -3 mapping port 6881 -> 192.168.10.21:6881
[01:43:47]  Unable to map NAT-PMP Port.

So uhm, "error -3" means something useful?

//edit

Still happening in 1.7 beta build 1875... Is there any progress, or more info you need from my end, because I'll happily provide it.