It seems that Boxifier does not sync with Dropbox. There is a minus icon on top of the 2 folders that I would like to sync. These folders are on an external drive.
A minus icon suggests that folder is unchecked in the selective sync settings in Dropbox.
Did you by any chance uncheck the Boxifier folder in the slective sync settings? If so, please make sure that you leave it checked otherwise the sync won’t work.