Acer PD724 series - Manual (Page 33)

... English
User Controls
If administrator forgot “Administrator Password”,
do the following to retrieve the “Administrator
Password”:
1.Press “MENU” for more than 4 seconds when
any of “Enter Password” or “Enter Administrator
Password” dialogue is currently displayed.
2.Write down the “Unlock ID” and contact with
Acer service center. They will give you new
Administrator Password according to the Unlock
ID.
3.Once the new “Administrator Password” retrieved
from Acer has been logged into the projector, old
“Administrator Password” will be replaced by the
new password.
Reset
Press the button after choosing “Yes” to return the display
parameters on all menus to the factory default settings.
Management
(Computer / Video
Mode)