WinXP lost TCP/IP?

Earlier I had no problem playing multiplayer games over the Internet. Now when I try to start a multiplayer game with TCP/Ip i get problems.
In Heroes of Might and Magic 3 i receive the error: "Error initializing TCP/Ip connection, try again", in Disciples 2 the option for TCP/Ip doesn't exist anymore, only hotseat. I can play Unreal Tournament using Gamespy Arcade, but that uses the IPX protocol.
All other communications works properly, except that I can't send/receive video in netmeeting.
I don't know what has happened, I tried installing XP again (As upgrade) but the problem persists. I use a ADSL connection, no router or firewall.
Help...

I't was quite some time ago that I played with TCP/Ip so alot has propably happened, but I don't knoww all (alot of installeds/uninstalls etc).
There is no problem in pinging the gateway, the TCP/ip connection problem is not random but persists always as i start a multiplayer game.
ICQ, Direct Connect, Audiogalaxy, Pop3/SMTP all works properly as does my ftp server.


* Very quick response to my question though, ! *
<P ID="edit"><FONT SIZE=-1><EM>Edited by Ruatha3 on 05/02/02 07:03 AM.</EM></FONT></P>

Alas, the problem does not seem to be restricted too anyone game but to all games(?) I have tried, there seems to be something that games does to check the TCP protocol that has been disturbed on my computer.
I have searched for information about not being able to use TCP/Ip with both games but comeup with nothing. So it doesn't seem to be a problem related to those games
I have tried three versions of Heroes of might and magic (Standard, Shadow of death and armageddons blade) I don't think I have any other game that uses the TCP protocol.

Is there any program that checks the network connection for problems, some kind of diagnostics?, I will look on the net for such a program now.

Thanx for your reply, any more ideas are welcome.

<P ID="edit"><FONT SIZE=-1><EM>Edited by Ruatha3 on 05/02/02 03:28 PM.</EM></FONT></P>