A few weeks back my wireless network stopped showing up as an option to pick from. Not just for one device, but all of my devices that use wifi. This includes my phone, laptop, and Xbox. My roommate who also lives upstairs told me she can't connect any of her devices to it either. My down stairs roommate is able to connect his devices though. In the meantime I've been using xfinitywifi for all my devices. Xfinitywifi is a good replacement for browsing the web and streaming videos, but the connection isn't good enough for playing online and downloading. 

Does anyone know what he problem might be? I've tried google searches and I can't seem to find anything. Of course I have reset the router numerous times with no luck. 

Derp nvm, can you access your router through the IP address?

By physically connecting to it via Ethernet Cable?

-Is there a light on the devide showing that you have or dont the WIFI on?
-if you access the device is the "hide wifi SSID" checkbox checked?
-Can you check if the correct freq is selected (i.e. 2.4 GHz ir 5.2 GHz)? some devices dont support 5.2
-Can you add it manually to some device (like your laptop, Cellphone)?

I'm not sure how to access the router though the IP address because it's not showing up on any one's devices and it doesn't say it on the router itself. I just found out my downstairs roommate uses xfinitwifi as well. 

I live upstairs so it's not realistic for me to connect via ethernet cable, or else I would have done that a long time ago. 

Btw it's a router/modem combo device. What I'm probably gonna do is, because I'm pretty damn sure it's something wrong with the router, I'm going to sign up for comcast myself that way we get the new customer deal, and we will get a new router. 

Xfinity always gives me issues.

Always disconnects and sometimes just goes completely whack.

-The light flashes 
-It's not letting me go to the website to check
-Not sure how
-I tried, but it didn't connect

I do appriciate the help

Have your tried the basics of powering down the modem/router. Or resetting it to default? Also, still check it with a wired connection. Just to make sure wired ports are functing too. Use a laptop etc.

Maybe you should try in the first place to get an ethernet cable, in order to connect and access the WIFI router/AP. Check for the model online, to know whats the default configuration webpage (i.e. 192.168.1.1) so you can go there and check those settings about freq, or SSID name...

If your other roomie has a working connection, something tells me he changed configuration and doesnt want to share wifi...

For some reason I wasn't able to go to configuration webpage and I tried to other address like routerlogin.net, etc. 

I was actually wrong and he is using xfinitywifi as well. He's been having the same issue for awhile. 

I'll give it a shot. Let you know if it works.