Boogy
If you mean Tools>Compare and Merge, this is available only with shared
workbooks.
It is a feature used to compare different versions of a shared book.
See Help on "merge and compare" for more info.
Gord Dibben MS Excel MVP
>How do I activate the xls feature to combine and compare workbooks? I want
>to combine workbooks and be able to compare the data in each; and show
>changes between the books.