Friday, July 2, 2010

MSN Messenger messages not delivered in routed network

For months I've had this same issue:

Windows Live Messenger fails to deliver some messages without ANY warning of failure.

After lots of troubleshooting, I've decided to foward port 1863 to the WIFI router that is directly connected to the internet access modem router and what do you know, it worked!

Turns out some of the messages we lost in the first router. Since there are two separate networks (the WAN and the DHCP internal private network), sometimes packets just didn't know where to go.

Modem Router Network:
WiFi Router Nework: (WAN) / (LAN)

TCP Port: 1863
Forward to


  1. gosh
    thanks for telling
    i have been googling up and down for answer..
    hope it will works

  2. right now I'm actually forwarding all ports (from 20 to 65535) from the internet access router to the service router, both udp and tcp. by this, I'm telling the first router just to act as bridge, since it does not have that option in the web configuration.
    I'm sure forwarding tcp port 1863 will make msn work. Now I receive instantly all the messages and none are left unsent/unreceived.