You can update the format of the MDB files using Access 2003 or later, or move the databases to another supported vendor database before upgrading Rational ClearQuest and then move them back to Access that is available with Rational ClearQuest after upgrading.
If you do not need the test databases and want to delete them, use the Designer to delete the databases before upgrading Rational ClearQuest. In the Designer, click Database > Delete Databases.