Hmm, can you check up on the drivers? what does it show when you plug in the phone while the power is off?
I have no idea wether you're new to rooting etc or not, but have you checked these 2?
ADB Debugging on: settings > options for develope...
does the update push the stock recovery as well?
and root is lost right?
Yes you will lose root.
But you can obtain root easily using this method.
Just download the DebugfsRoot_Generic_v2.3.zip file from here
Check the device firmware type by going to Setting - about tablet - built number
Download the right firmware pack for your device.
Now extract the zip fil...