It's a somewhat tricky procedure to get it into its recovery menu to reset it, may take a few tries to get it right but here's how...
WARNING THIS WILL ERASE ALL DATA, PICTURES, AND SETTINGS!
1.)Power tablet off
2.)Press and hold power + volume up
3.)When the "Insignia" appears, release power button but continue holding "vol up"
4.)A small list of words appear in top left corner
5.)Release volume up button
6.) Use (volume down) to select "recovery Kernel", then press (volume up).
7.) Wait a second, and a robot will appear.
8. )When the robot appears, press both the "Vol Up + Vol Down" buttons together... this may take several attempts to get it but eventually you will get a list of commands, one of which is "Wipe data/Factory Reset". Highlight it using the "Vol Down" and then "Power" to select it.
9.) Then you'll see a confirmation screen, so again "Vol Down" to move, and "Power" to select.
10.) now the system will reboot, this will take a couple minutes