How can I open a file to make it reaable on my computer?

I initially typed an essay on another computer and sent it to my home computer. My computer is more updated than the computer I typed my essay on but everytime I try to open up the doent a box that says,"File Conversion" pops up and it tells me to select an encoding that will make my file readable- the problem is none of the encodings make my essay readable, instead a few symbols come up...Can anyone please hlp me??