PowerPoint always trying to repair files

I have Microsoft Office 2013 and whenever I use PowerPoint, it keeps telling me that it is attempting to repair some files that I do not think they have a problem. Even the other day, I copied a file that was working well on my friend’s laptop and when I tried opening it with mine, PowerPoint kept trying to repair it for like 20 mins and eventually failed to open it. What could be the cause of this problem? Is there an easy way that I could implement to repair it? Please advise me how to go about it.
