I've run into this issue before and it ended up being an error with the Excel sheet. Emma Support should be able to help walk you through a few different troubleshooting options over the phone (+1.800.595.4401).
Thanks for jumping in with some sound advice, Bethany! Giving us a call here in Emma Support is definitely the best way to get timely assistance, but if you want to try to figure this out on your own, then take a look at this article from the Emma Resource Center dedicated to troubleshooting imports and let me know if you have any additional questions. - Thanks!