Double Entries in Excel

[S1L1Y1]

I have Office XP. I am working with Excel How can I check if I didn't enter
something twice? I found that I entered many rows twice. It would take me at
least an hour to go through the whole file.
Sol

 

[Niek Otten]

http://www.cpearson.com/excel/NoDupEntry.aspx

and

http://www.cpearson.com/excel/deleting.htm#DeleteDuplicateRows

 

[S1L1Y1]

Thank You. where can I get the validation tool or how?

 

[Niek Otten]

It is a standard feature of Excel. In HELP, type "Validation".