Can't play on Modded servers ( ONLY )

[5STAR]

Hey all

Recently a buddy of mine is having a issue where he can't play on MODDED servers.So I'm stumped at trying to fig this one out.

He has no problem playing on regular or UN modded servers AT ALL. It's only with servers with a MOD on them. He can connect, and DL all maps and the mod. But after playing a minute or so he just stops and ( FREEZES ) This only happens on W@W, all other games are fine.  :?

He has reinstalled the game 3 times with all the patches and no errors at all.He exceeds all the  system requirements. We have defraged, rolled back drivers NOTHING.

Anyone ever heard of this ?

I would like to get this guy on our modded server but, I'm stumped  

[stufz]

Could use more info:

OS
PC Specs
location
connection type
router make n model
other games played - including custom / modded

My first guess is the DirectX -

Download the first link and run it before getting the 2nd linked download:
This download will ask you for a folder - so make a folder called directx when asked to make a folder - and extract the files to it, Then run the dxsetup.exe

http://www.microsoft.com/Downloads/details.aspx?FamilyID=9226a611-62fe-4f61-aba1-914185249413&displaylang=en
 
Now download this link and run it - dxwebsetup.exe

http://www.microsoft.com/downloads/details.aspx?FamilyID=2DA43D38-DB71-4C1B-BC6A-9B6652CD92A3&displaylang=en
 
The location thing - I have a buddy in Alaska with a very thin DSL connection. His ping to a Dallas/Chicago server witll be over 150 but the latency is horrible. I've seen his ping run upto to 2000 on Teamspeak at night.  

Anti-virus - if its running while gaming, turn it OFF.

Router - There are some dodgy routers out there that have issues - go here for setup for specific games for specific routers - http://portforward.com

Also - I have several buddies that live in the sticks - some on dsl others on cable - and on a custom / modded cod4/5 server, they will always get disconnected AFTER having downloaded the map/mods if needed or just connected to the server.  Don't know the fix but they're not freezing up, but just getting disconnected.

Hardware - I run an older vid card - the 8800 GTS - CoD 5 doesn't like any of the nvidia drivers above 185.85 - causes problems, vid glitching whatnot.  

There you go, that's some stuff to consider.