The company I work for is still quite new and has yet to buy a server or lease space from a managed host service. Instead, we are all using Dropbox to share our files. Dropbox doesn't play nice with databases and the only Dropbox file check-in/check-out program I know of, NotifyBox, doesn't work with Access yet. Until we get a server, we don't have multi-user capability for Access databases. Anytime more than one user tries to write to the database at the same time, Dropbox will produce a new copy of the database.
As a temporary workaround, I am wondering if users can open up the database for exclusive access in order to prevent data collisions. I have already split the database into back- and front-end databases, with the back-end stored in the Dropbox folder and the front-end deployed to each user's local client. I can have users open their front-end databases exclusively, but I need them to be able to open the back-end exclusively as well. Any idea how I can do this? Alternatively, any ideas about best practices until we get a server, like procedures that our employees should follow to prevent data collision and loss?