Can't Delete The Desktop

I set up a wireless network that looked like this: Internet --> Wireles Router --> XP Desktop --> Printer| Vista Laptop This was all working fine until I started tweaking vista on my laptop and downloading vista updates. Then suddenly, my vista laptop can't detect the desktop, although my desktop can detect the laptop (although it can't access it). I've installed all updates for vista between installing the network and this problem. I've changed services in services.msc. Although I've changed it all back to what it was before. I removed some 'Windows Functions' from 'Control Panel/Programs/Programs and Features.