Microsoft Access Database File Format: What is an ACCDR File?

Microsoft Access Database File Format: What is an ACCDR File?

You may have come across the ACCDR extension file format option for a Microsoft Access database instead of the standard and more commonly used file extension ACCDB. So what is this file extension format?

Simply put, the letter ‘R‘ could best be denoted as the ‘run-time’ mode of your MS Access application which will lock the database as a ‘read-only’ instance from the design and general application.


The method is very straight forward! Just simply rename the file extension (once the database file is closed) to ‘.ACCDR’ via the O/S Windows Explorer. Make sure you can see the file extension view (search the web on how to switch this view on).

To open the newly renamed file extension will need to be carried out from either Windows Explorer view or an icon shortcut and not via the Microsoft Access database application’s ‘Open‘ command.

When you do this, you will note the interface will load the run-time application stripping out the ribbon bar leaving with a basic ‘File’ tab and very few options!


Microsoft Access Database File Format: What is an ACCDR File?

One important point to remember, you will need to make sure you set a start-up form to load when the run-time database opens as you will not be able to access any of the standard tools like ‘Open‘. This is set while the file is in ACCDB form via the ‘File‘ tab, Options (or equivalent based on which version you use).

At anytime, you can rename the file back to ACCDB and gain full functionality of Access and continue editing the design side of your database. Therefore, this is not really a secure way to protect your database file – just a quick and convenient way to lock out ‘unsophisticated’ Microsoft Access database users from wondering adding a layer of design protection at the same time.

If you want to create a stronger lock down version, consider using the ACCDE executable file which is a save as action in your application and strips out all design that makes a copy of the original ACCDB so you can still regain design control.

Both the ACCDR and ACCDE can use either the built-in Access run-time or the freely downloadable Access run-time (can be found from my Free Stuff page) for users who do not have a MS Access licence.

The ACCDE file format is intended for distributing to others whereas the ACCDR is for internal use.

Want to learn more about Microsoft Access? My eBooks is a good place to start 🙂

Leave a Reply

Your email address will not be published. Required fields are marked *