My phone won't install the apk file of an app I've owned before?

Since the newer version of facebook messenger doesn't work all too well for me, I went to a site that allows you to download older versions of apps and downloaded the version I had before I updated. When the download, I tried to install it and for some reason, my phone wouldn't. I do have "Allow installation of non-market apps" checked, I downloaded the file multiple times and it installed all the way through. Still, it just keeps saying,"problem parsing package". Is there anything I can do?