No Incoming Conns

[Themuddler]

Dear All,

I cannot get any incoming connections and get the red ! "not connectable" icon in utorrent. Downloading works but without incoming connections. The port check in the speed test dialog reports that my chosen port (36203) does not appear to be open. This never changes regardless of the steps below.

I've tried almost everything I can find on this site and portforward.com, or think of. Here's a summary:

Equipment: Windows XP, Belkin F5D7362-4 wireless G router+modem connected to pc by ethernet, no wireless connections to the router most of the time and never during testing.

Things I've tried:

Both DHCP and Static IP including restricting DHCP range lower than static ip address

Router firmware is up-to-date

Completely disabled: Avast anti virus, AVG Free, Windows firewall, router firewall all simultaneously.

Tried router "DMZ" option with all above software disabled.

Tried having Windows and Router firewall turned on independently and together with port forwarding for 36203 (both TCP and UDP) with pc having static IP then with DHCP.

The only hint I can get is from the router's security log but it's a little to esoteric for me to follow. Note that 192.168.2.4 is my pc with DHCP setup. I have tried this with a static ip too. Here's a sample in the hope that someone can spot my problem:

Apr 4 18:38:47 2007 Outbound Traffic Blocked - NAT out failed ICMP type 3 code 1 86.29.247.158->85.157.19.183 on ppp0

Apr 4 18:35:36 2007 Outbound Traffic Blocked - NAT out failed Packet not in tcp window: TCP 192.168.2.4:4959->217.44.58.176:14960 on ppp0 [repeated 5 times, last time on Apr 4 18:36:36 2007]

Apr 4 18:35:35 2007 Outbound Traffic Blocked - NAT out failed TCP 192.168.2.4:4959->217.44.58.176:14960 on ppp0

Apr 4 18:32:13 2007 Outbound Traffic Blocked - NAT out failed ICMP type 3 code 1 86.29.247.158->195.28.78.67 on ppp0

Apr 4 18:27:30 2007 Firewall Setup Firewall internal Firewall configuration succeeded

Apr 4 18:27:29 2007 Firewall Setup Firewall internal Starting firewall configuration

Apr 4 18:27:08 2007 Firewall Setup Firewall internal Firewall configuration succeeded

Apr 4 18:27:08 2007 Firewall Setup Firewall internal Starting firewall configuration

Apr 4 18:27:03 2007 Outbound Traffic Blocked - NAT out failed First packet in connection is not a SYN packet: TCP 192.168.2.4:3865->81.158.183.13:39843 on ppp0

Apr 4 18:26:05 2007 Outbound Traffic Blocked - NAT out failed Packet not in tcp window: TCP 192.168.2.4:3865->81.158.183.13:39843 on ppp0 [repeated 5 times, last time on Apr 4 18:26:53 2007]

Apr 4 18:26:04 2007 Outbound Traffic Blocked - NAT out failed TCP 192.168.2.4:3865->81.158.183.13:39843 on ppp0

Apr 4 18:24:15 2007 Outbound Traffic Blocked - NAT out failed First packet in connection is not a SYN packet: TCP 192.168.2.4:4423->61.95.203.233:62429 on ppp0

Apr 4 18:23:49 2007 Firewall Setup Firewall internal Firewall configuration succeeded

I called my ISP (tesco.net) and they insist that they do not block any ports or throttle bittorrent bandwidth. uTorrent statistics report that I have had >3000 outgoing connections and 0 incoming ones.

Is there any way to figure out at what stage the inbound traffic is being blocked?

All suggestions are gratefully received. Thanks for your time.

[kurahashi]

Were you changing the router settings while the time this log was produced?

[Themuddler]

Yes, I disabled the router firewall (other firewalls already disabled), tested the port, then re-enabled it. I wanted to minimize the time spent unprotected.

Just spotted lots of these too on checking a more recent log (firewall enabled but port forwarded):

Apr 4 23:24:19 2007 Firewall Error Firewall internal NAT Error : connection pool is full. No connection created [repeated 9 times, last time on Apr 4 23:24:20 2007]

Apr 4 23:24:19 2007 Outbound Traffic Blocked - NAT out failed TCP 192.168.2.4:1456->85.211.46.129:45256 on ppp0

Later:

Tried enabling upnp again and increased the number of reported items in the log.

Apr 5 00:19:17 2007 Inbound Traffic Blocked - Service First packet in connection is not a SYN packet: TCP 86.16.187.31:52181->86.29.247.158:36203 on ppp0

Apr 5 00:19:16 2007 Inbound Traffic Blocked - Service First packet in connection is not a SYN packet: TCP 149.135.29.104:1619->86.29.247.158:36203 on ppp0

Apr 5 00:19:16 2007 Inbound Traffic Blocked - Service First packet in connection is not a SYN packet: TCP 86.146.84.181:65246->86.29.247.158:36203 on ppp0

Apr 5 00:19:16 2007 Inbound Traffic Blocked - Service TCP 83.85.126.55:3552->192.168.2.2:36203 on ppp0

Apr 5 00:19:16 2007 Inbound Traffic Blocked - Service TCP 82.21.21.113:1386->192.168.2.2:36203 on ppp0

Apr 5 00:19:16 2007 Inbound Traffic Blocked - Service TCP 196.44.190.200:1540->192.168.2.2:36203 on ppp0

Apr 5 00:19:16 2007 Inbound Traffic Blocked - Syncookie protection TCP 172.143.218.139:1952->192.168.2.2:36203 on ppp0

Lots of this SYN packet stuff. I'm completely unfamiliar.