Why won't my computer recognize my device?

The problem you are having could be due to a number of reasons such as a faulty USB port, cable, or Micro USB board or un-updated software. Please visit the Nexus 7 (2nd gen) troubleshooting page for possible solutions to your problem.

Here is what worked for me; After I initially my tablet to my computer it worked fine until my computer updated. I tried everything except removing updates because I had no idea which was the problem. What worked was; with my tablet connected to my computer by USB cable, open my Control Panel, open the Device Manager, find my tablet in Portable Devices(in my case EGQ307) and right click on the device. It gave several choices, most of which hadn't worked before, so I tried the only one left uninstall. I then followed correct procedures for turning off and disconnecting my tablet. When I reconnected my tablet my computer immediately found and loaded the driver and my tablet worked with no problems. I still don't why it does this (it has happened twice) but at least this fix works.

Are you a new Android user? If so, this will be an easy fix. After you connect the tablet to a computer a notification from the top will appear and ask if you want to trust the computer. Just tap accept.

i installed drivers so computer recognizes nexus 7. i read that previous drivers need to be uninstalled before installing again then nexus root toolkit should work perfectly.