Hi there, interrobang!
Shoot, I’m so sorry for the trouble here. Seeing that sort of message would be jarring and the thought of losing data would certainly be scary. I can help you out here.
First off, please back up all of your files and your database. It’s always a good idea to do this when installing any updates or changes to a site.
Once that’s done, will you please confirm the version numbers you are using for the plugins? I see you noted that you are using the latest, but I want to make sure they are in fact the latest:
- The Events Calendar: 3.9.3
- The Events Calendar PRO: 3.9.3
Are those the same versions you are running? If so, please let me know. If not, please update to 3.9.3 of both plugins and let’s go from there.
Cheers!
Geoff