My daughter turned off her tablet during an update and it would not reboot. After hours of reading posts the only thing that has shown progress was this: I had to connect a usb keyboard to the tablet to access the recovery menu. (repeatedly pressing home to bring up the menu), I then used an sd card that i had to format on an android phone for the tablet to read it. i copied the update.zip "acer a500 4.010.38 com gen1" that i downloaded from xda developers to the card. Then loaded it into the sd slot. It appeared to be working, it recognized the card and the file and went through the install (displayed the no power off no reset graphic, which is the only graphic i have seen on it for days) so i thought it was working but then on reboot i got a red letter error that said boot verified failed. Suggestions?