copy only cells that are duplicates

[peng13]

Hello gang- first time poster, user of excel 2010.

Sorry if this is a stupid question, have been searching for the answer for quite awhile.

I have a spread sheet with 2 columns that I have applied conditional formatting to to find duplicate values. So the duplicate cells are highlighted in red now.

Problem - I want to copy only those red cells to a new column in a new tab, and am having a devil of a time figuring out. Best case would be some sort of formula I could use on the new tab&column to do this. Thanks.

[Pauleyb]

There is an easy way to remove duplicates, but you want to keep only the duplicates, so that is a little twist. There may be a cleaner method, but I would use a helper column with something like:
=COUNTIF($A2:$A$800,A2)
and drag that down.

Then highlight the helper column numbers, copy, and paste as values.

Then I would sort on the helper column. Then copy/paste the values from your original data that had a value greater than 1 in the helper column.