Sometimes, the OFF button of the OHP Remote Control may seem not to work, specially in new overhead projectors. When this is the case, do the following: 

• Aim the remote control to the OHP unit.
• Press and hold down the OFF button in the remote control for four (4) seconds .
• Wait until you see a message at the bottom of the screen saying "Please wait...."
• The unit will turn itself off at this time.
• If the unit still does not turn off, then it may be that the batteries of the remote control are low. 
  • In this case, have someone (a student) to reach to the OHP unit and press and hold the OFF switch on the unit.
• If the above step did not fix the problem, the only way to turn off the unit is by unplugging the power cord from the back of the unit.
• After the OHP is off, then you can proceed to reset the AMX and the rack unit and try using the AMX again.

This is actually a "feature" of the overhead projector unit designed to increase the life of the light bulb of the LCD unit. 

All OHPs are scheduled to turn off automatically after 5 hours of inactivity or at 11:00 pm (whichever comes first).