[weird problem]. network card won't save manual IP configuration

OS: Win XP Sp2
Computers:
1) This one ("server"), connected directly to internet and sharing internet with computer 2
2) The other comp. connected directly to comp1
NICs:
1) Nvidia lan (listed as: Nforce networking controller #2) >> Direct connection to internet (cable)
2) Realtek RTL8139 >> Connected to computer #2

Ok, I want to configure NIC 2 to have a fixed ip, for example 192.168.0.10. I click on properties > TCP IP and configure it manually (ip: 192.168.0.10, mask: 255.255.255.0). I click OK, it takes some seconds to close. When I enter again to see if it is applied everthing is set back to Auto assign again!. If I ipconfig, I get the IP listed as 192.168.0.10, and if I try to /release it I get "Adapter LAN is not enabled for Dhcp.".

Why can't it save my config? :S

 

If you want to share a connection this way you need to use Windows ICS to do the Routing, and ahve to assig an IP that would be compatible with ICS workings. http://www.practicallynetworked.com/sharing/xp_ics/

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