I have the same problem as Erika:
"My Box drive wasn't syncing properly on my macbook pro so I deleted the app and all Box related files from my Macbook pro. Consequently, I downloaded the new version of Box (v 2.18.117) and after attempting to open the app the following message prompted: "You installed an older version of Box Drive on top of a newer version. Please install the latest version of Box Drive. If the problem persists, please contact Box Support to further troubleshoot the issue."
I was also getting a message to enable a Box extension in System preferences> Security and Privacy, but I don't see such option to do it.
I would appreciate your help. I have contacted the University IT and spent 2 hours on the phone with Apple service. Nobody could help me with this problem.