This is a very difficult thing to do in Excel. I think you have to write
some VBA to do it. Maybe you can export it to an access database for
example, and then retrieve the values with a group-by query. This way
the database engine solves your problem.
Select the range, use Data/Filter/Advanced filter
check Unique Records Only and "Copy to another location"
Put in an address to hold the result, eg[F1] then click
OK. When you're done, you will have the unique records in
the new place.
You can delete the original range or not.
