VB6 /Access 2000 - unrecognized format

I have developed several applications using VB 6.0 which read and write data into Access 97 database tables. These have been working with no problems. Now we want to upgrade Access 97 to Access 2000, but upon experimenting I discovered I get an error stating unrecognized format when I run the applications using these converted databases. Any ideas how I can get my applications to work if we upgrade all the databases to Access 2000. Presently these applications are used on computers running Windows 95, 98, ME, NT, and 2000; all applications were written using VB 6.0 Professional version; and all databases were developed using Access 97. My company wants to upgrade all the computers to use the Office 2000 suite but can't until I resolvethis problem. Any help would be greatly appreciated.