Rather than have multiple copies of a database, and produce lots of work for yourself to update/merge them, it is much easier to share just one copy between all of the users.. but how do you do it?

Getting the file ready
As Access databases are actually files, the first step is to place the file somewhere that everyone can get to it. The usual way is put it on to a server, but it can be on one of the computers instead (but the computer must be turned on for anyone to use it!). Either way, we will refer to the name (or IP address) of this computer/server as ServerName.

The .mdb file must be placed in a Shared folder, otherwise people will not have permission (from Windows) to use it. You can set this up in Windows Explorer, right-click on the folder that contains the file, and select "Sharing" (or "Properties" -> "Sharing"). On the screen that appears you can enter the name of the Share (which you need to remember for later!), and set permissions for one or more users/groups. Note that you will probably need to change the permissions to allow "Change" or "Modify" (even if you only want the user to have read-only), and do the same on the 'Security' tab.

You should also set permissions on the file itself, which you can do by right-clicking on it, and selecting "Security" (or "Properties" -> "Security"). Select the relevant user/group, and tick the appropriate boxes (you may need "Change" or "Modify").

Well that's the file ready, how do we use it?
It depends on what you are doing!

If you want to open the file from within Access, you will need to enter the file name (and location) like this:

If you want to have a short-cut to the file (so it opens in Access), specify the file using the same format as above. If you want to find the file in Windows Explorer, simply enter \\ServerName\ShareName in the Address bar.

If you want to use the database from code (or in the properties of a control, etc), again just change the filename/path to the format above.