An .mdb file contains Jet elements (tables, rows, columns, data types,
constraints, indexes, stored queries, etc... oh yeah, plus the data in
the tables) and may contain MS Access-specific elements (forms,
reports, etc). The Jet elements are accessible outside of the MS
Access UI, the MS Access are generally not. Subject to permissions, an
Excel user could open an ADO connection to the .mdb and make changes
to the data or schema. It's not just MS Access applications that use
Jet databases! If you don't want certain users (or applications) to
make changes then revoke their 'write' permissions.
Jamie.
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