How do you get rid of "MegaBackup"?

I'm not sure how it got there, but it is a program that automatically downloaded on my computer, which is giving me problems, and I don't know how to get rid of it. I've tried moving it to the trash and it just goes back to its spot. I've tried opening, force quitting it, then moving it to the trash and it didn't work. I'm not sure what else to do to get rid of it. Please help! Thank you!