Pop up not working

I've been building a new website for our organization on a different server than our current site. I had been using the Pop Up plugin successfully there for months. When I transferred over the wp-content folder to the current site though, the Pop Up plugin no longer works. Nothing happens.

The Wordpress versions are the same. All the rest of my WPMU plugins work fine. There is one another plugin that I use though that is encountering problems since I made the switch too.

I even did the update today for Pop Up and still doesn't work. Any ideas on why it doesn't work?