Converting a Microsoft Access Database to an MDE File:
The situation may arise when you quickly need to secure and distribute
a Microsoft Access database that also contains Microsoft Access VBA
code. You will protect the database from editing by restricting the
database users access to the design views, however you will need to
allow the users to process their data as normal.
It may be that you haven't got the time to fully create Microsoft
Access User Accounts or to set Microsoft
Access Security Permissions. By knowing what can and cannot be
done by using the Microsoft Access MDE file format, will allow you
to make a decision and to quickly release a secure database to the
Microsoft Access MDE File Format
The MDE file format is a special extension of the standard Microsoft
Access MDB format, and is used to distribute an application. An MDE
file compiles all of the modules, removes all editable source code
and compacts the database. The resulting MDE file allows the database
users to perform normal database operations, however it prohibits
any changes from being made to the objects that support, or the code
that runs the application.
Figure1: Creating an MDE File
Benefits of an MDE File
There are various benefits to be had by creating and distributing
the database as an MDE file:
- Reducing the size of the database - the size of the database will
be reduced due to the removal of the code, so memory usage is optimized,
which will improve performance.
- Allowing VBA code to run, but protection from the code being viewed
- Security of objects without requiring additional Microsoft
Access user-level security to be set.
- Allowing database users to update data and run reporting options
without having to provide the full database.
Forms and Reports in an MDE File
By converting your Microsoft Access database into an MDE file you
will prevent your database users from tampering with your VBA code.
When a user accesses an MDE file, they cannot:
- View, modify or create Microsoft Access forms in design view.
- View, modify or create Microsoft Access reports in design view.
- View, modify or create Microsoft Access modules in design view.
- Add, delete or change references to databases or to object libraries.
- Change any VBA code - there is no source code available.
- Import or export any forms, reports or code modules.
MDE File Requirements
There are some requirements to saving your Microsoft Access MDB
file as a Microsoft Access MDE file, and the following
- You must have password access to the Visual Basic code in the
- You must save all references to other Microsoft Access databases.
- You must have removed replication from a replicated database.
- If you want to remove user-level security options, you must do
so prior to converting the file to the MDE format.
- If your database does have user-level security and you do need
to preserve this, you must do:
- Be a member of the workgroup that defines the user accounts
used to access the database, or that was in use when the database
- Have Open/Run and Open Exclusive permissions for the database.
- Have Modify Design or Administer permissions for any tables
in the database, or be the owner of any of the tables in the
- Have Read Design permissions for all objects in the database.
How to Convert a Microsoft Access Database to an MDE File
Once you have determined that you meet the above criteria for converting
an Access database in MDB format to the MDE format, it is a simple
process to make the conversion happen. You will need to perform the
- If necessary, convert the database into the latest Microsoft Access
version - if the file format is Access 2000 and you are working
in Microsoft Access 2003 you will need to convert the database file
format to Access 2003:
- From the Tools menu, choose Database Utilities » Convert
Database » To Access 2003 File Format.
- Navigate to the database that needs to be converted and click
- Enter a name for the database and click Save.
- Click OK to dismiss the message box.
- Open the database to confirm the name change.
- Choose Tools » Database Utilities » Make MDE File.
- Select the database to be converted and click Make MDE.
- Confirm that the file has been converted to MDE and click Save.
- Open the new file, and confirm that the Code toolbar is disabled
and that the application works as expected.