You cannot revert, or downgrade, a QuickBooks Enterprise Solutions (QBES) company file to QuickBooks Pro or QuickBooks Premier (Pro/Premier). When upgrading to Enterprise from Pro/Premier, the database structure expands to accommodate the additional features of QBES. Once the database has been expanded, QuickBooks cannot return the file to a lower edition. QuickBooks Pro/Premier cannot recognize the QBES file structure.
You can start a new company data file: