1. Open Microsoft Excel.
2. Click the 'Office' button in Microsoft Excel. It is in the left, top corner of the program.
3. Click 'Excel Options' from the drop-down menu.
4. Click 'Add-Ins' from the menu along the left navigation pane in 'Excel Options' dialog box.
5. Click the drop-down menu next to 'Manage' and select 'Disabled Items.'
6. Locate and click on 'dgnexcel.dll' from the list of disabled items.
7. Click 'Close' and 'OK.'