Access 2002, and getting data shared across applications

[Carly]

I have a program which we bought that is a billing program
that doesnt have all the reports that we want. What I want
to be able to do is to get at the data using a form that
we can use to both update data as well as see certain
aspects of our data. Sounds simple and straight forward,
but when I try to use access to open the database it says:

1) The database is locked. I then close our billing
software and then get a different error.

2) It say's that the database is "Read Only". I go to the
properties of the database, and the Read Only box isnt
checked.

3) If I copy the database out of the application I can
read the data.

Any help would be great,

Thanks

Carly