Duplicate Preventer is a Microsoft Excel add-in that helps to prevent entering duplicate data while working in Excel. Duplicate Preventer integrates into MS Excel by placing its toolbar into the Excel toolbar area. The add-in allows defining where to check for duplicates in the active row, column or only in a selected area. The duplicate tracking is optionally possible with exactly the same data and data within different letter cases. Defined tracking options save and activate in one click when required. Follow the link and free download Duplicate Preventer now.