You have to re-fix your router's config.
Change the settings from "150 through 200" to "200 through 220" save it... reset it and then change it back.
Reason I say... the lapper is getting a "default" uPNP address and so is the other device. (Thank MS for pushing uPNP (which isn't "universal") and ZEROCONFIG (which isn't))
Either that or you've had your "network" stuff changed on you lapper.
Just use NetworkManager to setup your wireless and force it to make them "global" on your laptop.