Any idea how to add/remove base directories once the file is hosted on server?
You cannot add base directories on hosted file, but given your question you already found that out.
Option 1: Download the file from the server, do your thing on the local file and upload it back to the server.
Option 2: Close the file from the admin console to ‘unhost’ the file and use a copy of Filemaker Pro installed on the server to open the file directly from the database folder. This way it is local. Once done close the file in FMP and use the admin console to open the file again.
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