Why I am unable to factory reset my acer a500 table

Hi,

Here is how to do a factory data reset

Warning, this will erase all of your personal information, all stored contacts and any programs you have installed on your tablet

Power off the tablet.

Press and hold the Volume Up button.

With the Volume Up button held, press and hold the Power button for 3 seconds then release it. Continue holding the Volume Up button.

Once the tablet vibrates, switch the touch screen lock switch on and off repeatedly while still holding the Volume Up button.

Release the Volume Up button and stop switching the touch screen lock switch once the "Erasing Userdata..." message appears in the upper left corner of the screen.

Once the factory reset has been completed your tablet will load to the welcome screen.

Your factory data reset is complete. Now follow the onscreen steps to setup your tablet.