Clearing information in certain columns

[jolly_lolly]

I have a big spreadsheet that contains duplicate information in columns A & B
for seveal rows. The information in remaining columns is different. Columns
A & B may contain same information for many rows, then change. I have been
doing a clear contents on columns A & B with duplicate information. There
must be an easier method for clearing duplicate information without
disturbing information in rest of columns.

 

[Dave Peterson]

Chip Pearson has tons of ways of working with duplicates at:
http://www.cpearson.com/excel/duplicat.htm