1100MP Projector Remote Problem

I just hooked my computer, a MacBook Pro, to a converter and VGA cable to my classroom's LCD projector (the 1100MP Dell Projector). I am a teacher and inherited the classroom and projector this year from a teacher who left the school, so I'm not sure on all the information but know it had been used and worked in the past.  

Everything is working fine except on the Dell projector remote, I can't get the 'Next Page' and 'Previous Page' buttons to work. The light blinks when I press the remote, but nothing happens on the screen - the only way I can move to the next page on my Powerpoint slides is by doing it manually from the computer. Can you please let me know of what might be the problem? Either I have to change the settings on the project or maybe it is the preferences for Powerpoint to get it to respond. 

Please please help as I have my first day of class next week and it's extremely important that I be able to work the remote for my lesson presentations. 

Thanks, Andrew