can't find my own network

I built a new computer with built-in WIFI on the mobo. My old PC has a
router but when I use my new PC to find available wireless networks my
own network does not show up. Any suggestions as to how I can fix
this? It used to work on my wife's laptop (but hasn't since last
week).

Also, is there a way to set up Windows to automatically log onto my
wireless network when the computer reboots or starts up?

Would it do anything if I disconnected the router, removed the
settings on my old PC and started all over again?

Thanks!!

Eddie G