Is there an uncomplicated way to install a new factory image on a Google Asus Nexus 7?  The tablet in question has had several people erasing data and rooting it, so that nothing now works, other than the Google circles rotating around one another. We did manage to get to Recovery Mode and erase the data, following instructions we found online, but now Recovery Mode is also unavailable. I don't know what generation this tablet is, but the model number of it is ME370T.