Remove duplicates in Excel

From http://support.microsoft.com/kb/262277

1. Select the column titles above rows or records that you want to sort.
2. On the Data menu, point to Filter, and then click Advanced Filter. If you are prompted as follows, click OK.
   No headers detected. Assume top row of selection is header row?
3. Under Action, click Copy to another location.
4. Click to select the Unique records only check box.
5. In the List range box, type or select the range of records (such as A3:H10).
6. In the Criteria range box, type or select the same range of records (that is, A3:H10)
7. In the Copy to box, type the address of or select the first cell where you want the information to be placed. Make sure there is enough room so you don't overwrite pre-existing data.
   
   Note You can only do this in the active sheet.
8. Click OK.

Notes

If the first record of original data is duplicated, it appears twice in the new list. Just hide the first line.

If you perform the Advanced Filter command in-place, the sheet still contains all records. Duplicate records are hidden. To work around this behavior, point to Rows on the Format menu, and then click Unhide.