Duplicate Manager is easy to use tool for MS Excel. After installing it, you can see a separate menu in Excel 2000/XP/2003 and a separate Ribon strip in Excel 2007/2010 as shown below.
Duplicate Manager Menu for Excel 2007 or 2010 :
To remove duplicate records click "Remove Duplicate Entries (Keep First)" from Duplicate Manager Menu. Choose "Remove Values Only", if you want to remove only cell content or choose "Remove Entire Rows", if you want to remove entire row from the list.