When I have my Nexus plugged into my laptop it says that my USB Device not recognized.
-go to device manager
-locate Nexus driver
-right click on it and choose uninsyall (do not delete)
try this microsoft fix it
Hello, good question. I've had a lot of problems connecting USB devices to Windows systems in recent years. I'm not sure why this is, but it has something to do with MTP and the way Windows recognizes flash memory on-board many tablets, smartphones and media devices. It doesn't seem to be prevalent among USB drives, for whatever reason. I hope someone chimes in with a better fix than mine, though.
The first thing I would try is to go into Device Manager and check to see if there's any devices with a yellow icon over it. If there is, try uninstalling the device. Then proceed to go to "Action" (in the menu bar) and then "Scan for hardware changes". This should reinitialize the device and get it working again.
If that doesn't work, check on your Android device to see if it requires permission to connect as a media device.
Unfortunately, both these tips oftentimes fail. The most bulletproof method of connecting a Nexus 7 tablet (or any Nexus device) is by using the WUGFresh toolkit and closely following the kit's instructions for connecting a Nexus 7 via USB.
There's a variety of physical reasons that could impair a USB connection, but I would concern myself with the software side as that is the most common point of failure.