DSL Modem + Wireless Router
2 Laptops (A &B) need to connect wirelessly
A Connects wirelessly but B doesn't
B connects to internet wired - gets DHCP server
B's Wireless Adapter Card works on A
B cannot find DHCP server; assigns 169... address. Can't connect to internet

Connect, open cmd.exe

Ipconfig /release
Ipconfig /flushdns
Ipconfig /registerdns
Ipconfig /renew

Let us know what happens... give error messages.

Check to make sure Computer B doesn't have static IP, but is set to auto configure.