Acer F900 User Manual page 77

If your screen is responding to stylus
input: Go to Start > Programs > Utilities
> Default Settings. Read the warning
information and enter the security code
in the empty textbox. Tap OK to pro-
ceed.
If your screen is not responding to stylus
input: Press the reset button while hold-
ing the power button down. When you
see the Acer screen, press and hold both
the up and down buttons. You will see
a screen showing Clean Boot in red text.
Reset your smartphone 77