Is it possible to undelete a deleted program on the hard disc? Thanks for the help.

There is no built-in undelete feature, that's why you get the "are you sure you want to delete" warning. There are some computer-based programs that allow you to recover inadvertently deleted files off of RAM discs (they are rather hit or miss, however). But you are basically out of luck if you deleted it off your EH57 HDD, sorry.