Excel 2002 - Date format keeps changing
 

I have a user whose date format keeps changing.

If she puts 6/3/2006 (June 3, 2006) in a cell, it changes to 3/6/2006 ...
this does not appear to happen in all cells. She has one column where the
first few are okay, but then the cell format keeps changing.

I note that the "location" in cell formatting is set to Armenian (how do I
change to Canada)?

Thank you.