It is possible to remove duplicates in several ways in Microsoft Office 2007.

You can either remove rows containing duplicate values or highlight them, so you can delete them manually.
Please note that Excel 2007 does not allow you to review data deleted by using Remove Duplicates tool. To review data use Conditional Formatting tool to highlight and delete data manually.

To remove duplicate rows from an Excel spreadsheet:

1. Click in left top corner of your worksheet to select all cells

2. In the Data tab click Remove Duplicates

3. In Remove Duplicates dialog box select columns that you want to check for duplicate values. (This is the search criteria. Rows containing duplicate values will be deleted entirely)

4. Excel 2007 will display a message confirming removal of the duplicate values.

To highlight the duplicate values and delete the data manually:

1. Click in left top corner of your worksheet to select all cells (you can also select the column you want to check for duplicates)

2. From the Home tab click on the Conditional Formatting tool -> Highlight Cell Rules -> Duplicate Values…

3. Confirm to format the cells containing duplicate values.

4. To make reviewing duplicate rows easier sort the data so that rows containing duplicate values are next to each other for easy comparison.

5. Choose the column by which data is to be sorted

6. After sorting review the highlighted data and manually delete the rows by right clicking it and choosing Delete…