In previous versions of Excel, you can remove duplicate records by using advanced filtering, which not only retains the feature "advanced Filtering" in Excle 2007, but it is also more noticeable that Excel 2007 adds a "Delete Duplicates" button, which makes this easier and quicker.
First select all the cells that you want to delete duplicates. If you want to do this for all data, you can select a single cell.
Select the Data tab in the toolbar, and then click the Delete Duplicates button in the sorting and filtering area.
In the pop-up Delete Duplicates dialog box, select the field you want to check, and you will end up comparing only the selected fields. Here Select the latter three fields.
Finally click the OK button and the extra duplicates are removed.