Why does my internet always quit on me?

[Jay]

Usually at night, when everyone in my family is using the internet, it randomly stops working and my computer says "limited access" when I hover over my cursor on the wifi icon, or sometimes it just has a circle that indicates it trying to connect, but usually whenever 1 of the two happens, it takes forever to reconnect. I have to keep disconnecting and connecting, and even with an ethernet cable plugged (laptop to router), it does the same thing regardless. Earlier today I turned on wifi for my phone, and the same problem occured right when I connected to wifi through my phone.

I have comcast, and there are 4 other people in my family that are always using the internet.
I have a d-link DIR-655 router, and all computers in my house are windows. Whenever I click to troubleshoot/diagnose, nothing is found.

[TEX4S]

Might have an IP address conflict. But it would normally tell you so. Or QoS settings are prioritizing bandwidth hungry apps. There are many possibilities Without knowing the speed pkg, router, config - one can only guess.

On all of the windows based computers, have them do a ipconfig/release... then ipconfig/renew

[Tony RB]

"when everyone in my family is using the internet"

If several people are using wireless, you have congestion.

Other devices or appliances are putting out radio waves that cause interference. And these could be in a neighboring property. Or someone parked in a car nearby trying to eavesdrop.

You are competing with everyone else for bandwidth.

Any of them or all of them could be using a huge amount of the many megabits-per-second available, like watching a movie, opening several pages on a website, all of which contain a lot of advertising images and flash-animated ads.

Another possibility is the router has a bad port - the electronics on that port just don't quite work right. To test this swap the cables for your port and one of the others.
This won't work for wireless, though.