How to delete a sheet if the 'Delete' is grayed out from the popup menu in Excel. 1. On the Review tab, click 'Share Workbook' in the Changes group. 2. On the editing tab, uncheck the 'Allow changes by more than one user at the same time. This also allows workbook merging'. 3. Click OK in dialogue box. 4. Verify that the delete menu is enabled from the popup menu.