Multiple MSDE Databases on one computer

It is not that complicated. I’m using SQL Server myself, but it is no different with MSDE. The only reason why a database gets overwritten, is if you keep the same name.

Simply chose a different name (as opposed to the default PMDB) when you run the installation Wizard. You will then notice that the next two fields in that dialog (that list the Data and Log file addresses) change automatically to reflect the different name. (An earlier dialog will have asked you whether you want to include the sample data, or just create the database.)

Then when you login, select the ellipsis that is to the right of the database name. Use the option to create a new alias for the new database. (I use the same name as the database.) Thta’s a one-off step. For future logins all you need to do is to select the other database from that same dialog, if it is not the last database that you used.