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.... All users are located in the same room, on the same network, and all stations are logged in using the same login/password. We are running directly off the server (4 Apple monitors per station connected to the server, no tower in between the monitor and server)
It's not about which network they are on. It's about which file they are accessing and which application they are using to access it. If what you say is true, then Excel allows collaborative access to its spreadsheets. I did not know that Excel allows this. Clearly, Numbers does not.
 
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