Network Not working

So, my mom has been using NETGEAR for her wireless router and lately, even though the cable modem is on and working and the wireless network is showing up, my mom's computer won't connect to it. When she tries to reinstall the software for netgear, it says there's some sort of internal error and won't save the profile. I know it's not the computer, because it'll connect to other networks, just not the netgear one. I've also gone to my mom's house with my laptop and it won't connect to netgear either. I honestly think it's just the modem not working because the lights that blink on my modem at home aren't blinking on her's, but she says it's always been like that and worked so I guess it's something wrong with the wireless router itself? Basically I've used what limited computer knowledge I have to try and fix it, but it clearly hasn't helped. Any suggestions?

Jam it back in, in the dark.

Thanks for your guy's help but I got it fixed. It was just the router that wasn't working, not my mom's computer or anything.

There's nowhere I can't reach.