Alright I own a SpeedStream 5100,

Which is connected to my Linksys BEFSR41 (ver 4.3)

And connected to my router is my Xbox 360, and my PC. (Via Ethernet)
 
I'm going to try and narrow this down,
Say I have friend A, B, and C.
 
I can play with friend A just fine, no lag, no problems, etc.
But I cannot connect to friends B and C.
 
So we thought it was a minor problem,
And friend A, started a game, and invited C.
They were in the lobby, everything was cool.
Friend A invited me, and I couldn't connect.
So C leaves the game, and A reinvites me.
I join his lobby just fine, now A invites friend C.
Now C can't connect.
 
(Note: We tried this same thing, only by using B instead of C )
 
Now this is what I think is making it a router problem.
 
Ok so,
My friend tells me,
Have you opened your NAT?
I do so, then on my router status page, it says Connected,
As normally.
Then I attempt to log back on MSN, it will not let me, it's acting as if there is no internet connected.
Can't go on any webpage, nothing.
But I can access my Router Settings page, and on the Status page,
It says Connected.
I try logging into Xbox Live, and it's acting the same way.
 
(Note: My Computer has no internet problems like this, unless I disable NAT)
 
So I re-enable my NAT on my router, and disable all other security settings that could be blocking my connections with other friends.
 
And Still,
No Dice.
 
So this is my only option, I can't open my NAT due to me not able to do anything internet related, afterwards.
 
Thanks for reading, and help if you can!

Bump.

have you installed ipx in all computers, you can do this in Local Area Connetions Properties.
Also I find if  the server computer enable dmz host helps, last is use the port fowarding to open the recommanded port for that game.

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WAITING FOR THE NEXT MOMENT TO STRIKE

 

well only one computer is on the router, soo it's just the PC, and my 360.
DMZ is infact enabled
and iunno whut IPX is

IPX/SPX?
Client and server packet exchanges Needed for home Lan/Network gaming
 
 

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WAITING FOR THE NEXT MOMENT TO STRIKE

 

I didn't find anything for IPX/SPX anywhere in my router settings.

Forget IPX! Try connecting your PC directly to the SpeedStream and see if it works.
 
Grumpy

Works.
However 360 to Speedstream does not

Did you power cycle the Speedstream after connecting the 360? Is the 360 set for DHCP?
 
Grumpy

I saw nothing of DHCP on 360 settings, wut you mean by power cycle ?
Iunno, haven't tried it.

bump for great justice