>> On starting on either a Windows Server 2008 R2 Standard or Windows >> 7 machine, it comes up with an error message: Address not available >> (#10049 in setsockopt(IP_ADD_MEMBERSHIP)). > >MSDN says: > >IP_ADD_MEMBERSHIP - WSAEADDRNOTAVAIL - Do not call IP_ADD_MEMBERSHIP with >the same group more than once on the same network interface. > >so maybe you can not multicast on UDP and TCP at the same time on the same IP.
In netstat -a output I am observing to the contrary for another program that does this successfully on all 3 versions of Windows. (Aniazpopup - free off internet). The one difference I can see between my program and others is the local port is set to 0.0.0.0 instead of the machine's IP address. I've looked at that MSDN page previously and not sure what it means by "same group". Doesn't seem to mean same port. I would think I'm not actually multicasting on the TCP server socket though - didn't think that was possible, hence the UDP usage. Would this have any link to IPv6 changes? My XP box is still pre-IPv6. Stephen -- To unsubscribe or change your settings for TWSocket mailing list please goto http://lists.elists.org/cgi-bin/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be