Hola compañeros.Ya encontre la solucion y he quitado el root a mi tablet.Dejo aqui el enlace por si a alguien mas le hiciera falta.Saludos.
http://androidflip.com/how-to-update...tory-firmware
ADDITIONAL OPTIONAL STEP
In some cases flashing previous firmware leaves data partition intact.
I suggest to clean it by booting with [vol down] and [power] pressed (you will see the info about the rom). Than wait until the screen with android and wipe data appear. Select wipe by switching with [vol down] and accepting with [vol up] pressed two times. It mostly happen when downgrading to HC from ICS.