I am wondering if it is possible to write a batch or VB (or whatever type) executable that will run on WinXP/7 that will perform a check and then run a file if the check passes:

Check a folder for the existence of file xyz.laccdb.
If the xyz.laccdb exists generate pop up a message saying the database is already open; when the user clicks OK - end the batch
If the xyz.laccdb file does not exist in the folder, open xyz.accdb

This is to allow multiple users to share access backend via Dropbox.

P.S. I know there are safer ways to share the data, with SQL etc. But if this can work, it is the simplest solution for our application, which is used by a limited number of trained users sharing the db...

Never mind - I got my batch file to work.