from Garry's book on Access Security
· If you want to secure the forms, reports, and modules in your database, there is no better and quicker way to do so than to convert your database to the compiled format, called the MDE format. Before you do that, you need to
· Split your database into two databases. The first will hold all your software (queries, forms, reports, macros, and modules) and the second will hold all your data and relationships. … see Let's Split
· Make sure that users are not doing legitimate development in the live front-end database.
· You will need to have well-established control over who develops the front-end database and where that development takes place before you embark on using the MDE format.
· Ensure that development takes place on a computer drive to which the database users do not have access. To make an MDE-format database, all you have to do is choose Tools | Database Utilities | Make MDE, and you will have your MDE-format database.
If you are unsure whether the MDE format database will suit your needs, use it yourself as your production version. Once you have completed your test, direct a small number of users to try the MDE version. Generally, switching over to the MDE format is quite simple as long as you have good control of front-end database development. …
CAUTION The MDE format will not provide any security for your tables, queries, or macros.