Laptop Wireless No Longer Working

About a year ago, my father purchased a Compaq Presario F572US Notebook PC (Vista), and I set up a wireless connection to our Linksys BEFW11S4 router without trouble. Unfortunately, he came to me the other day and told me that the laptop had lost connection to the internet, and that he tried to fix it, but couldn't get it to work. I took the laptop and found that when I tried to "connect to a network", I was told that "windows cannot find any networks". From there, I clicked on "diagnose why Windows can't find any networks", and the laptop proceeded to tell me that "This computer does not have a wireless network adapter installed and configured". So, I went to the Compaq website and found the Broadcom wireless drivers, which I copied to a disk and installed on the laptop. Upon a quick restart, our wireless network appeared, and the router connected to the internet. Satisfied, I shut the laptop and brought it into my dad, but somehow, once the laptop was opened, the problem re-emerged and no connections were found. Since then, I have attempted to restore drivers for both the Broadcom and NVidia network programs, and even restored the laptop to its factory shipped settings, but somehow, the problem persists. I'm out of ideas and would very much appreciate any input. Thanks!