arduino board model due R3-E isn't recognized on USB

We are new to arduino.
We plugged our Arduino Due R3-E in to the computer for the first time to get started,
We put an LED in holes 13 and GND, and it started blinking like it should.
Then my dad found and pressed the erase button on the board...:'(...
Now when we plug it in it to the USB the computer does not recognize it at all. The green "ON" light and amber "L" light turn on steady.

We have performed the loop-back test, and at step 5 the computer does not see that a new device has been plugged into it on either my chromebook or my dad's PC laptop.

Using the Codebender.cc IDE on my school chromebook, I am able to upload sketches to my sister's (non-Arduino branded) Uno, so it seems like something is wrong with my Due.

Did we break it? What should we try next?

Thank you and Happy New year
Daughter
-Daddy&Daughter 'Duino Team