Office challenge: Why does Excel change dates when I copy a sheet to a new workbook?

This week, test your Excel skills by identifying and remedying this troublesome date behavior.

Copying or moving a sheet to a new workbook is a simple task, usually. But, suppose a simple copy task ends with a call to you for help because the new workbook shifts each date value by four years and a day! For instance, the new workbook converts the original date 5/2/2012 to 5/1/2008. What's happening and can you find a happy ending for this user?

By Susan Harkins

Susan Sales Harkins is an IT consultant, specializing in desktop solutions. Previously, she was editor in chief for The Cobb Group, the world's largest publisher of technical journals.