[AccessD] ODBC Setup Problem - New Access 2007 Application

All,

I have started to deploy a new Access 2007 Reporting Application on
about 15 PCs.  The data lives on a FireBird Database and is accessible
via ODBC.  I have been running tests for several months and everything
works great.

Recently I started installing the application of our users' PCs.  Things
went nicely on the first four PCs, but on the fifth one, I hit a snag
with setting up ODBC.  I then tried the exact same setup on 4 other PCs
and I am running into the problem.

I have downloaded the Firebird ODBC driver installation file and stored
it on our server.

I have run numerous tests with this install file.  It works on some PCs
and does not work on others.

All of the PCs are running XP SP3.

The install of the driver appears to work fine.

When I go into the Control Panel / Administrative Tools / Data Source
(ODBC), I can see the driver.

I then try to add a new System DSN.  When I try the "Test Connection" I
receive this message
 "Open database 'Y:\Database\demo\EJDB.FDB' failed" 

I have spent about 12 hours trying many different things and am running
out of options.

I have logged on as Administrator and the problem still surfaces.

I have shut off the virus detection software - no luck.

I have rebooted the PCs -no luck.

I must be missing something.  Has anyone else ever run into something
like this?

Thanks,
Brad

PS.  I have read about DSN-less connections, but I have never
experimented with this approach.
Perhaps someone could post an example of how to do this.  This might be
the approach that I will need to take.    Thanks!