Hi Mary,

Ensure that you have a backup of your workbook before doing any of the
following because I cannot be certain that my assumption of text is accurate.

I suspect that the dates in your worksheet are text and if my assumption is
correct then you should be able to use Text to Columns to fix the problem.

Select the column of dates.

Select Menu item Data - Text to columns (or in xl2007 Ribbon Data then Text
to columns)

Select Fixed width then Click Next (Data preview is displayed.)

Click Next again.

Another data preview should be displayed with black background (selected)

Under Column data format section click date button.

Click the drop down against date and select MDY (That is the date format of
your existing data)

Click Finish.

Your column should now be valid dates but in the wrong format. (MDY)

Select Number format and format the dates in your required format. (DMY)

--
Regards,

OssieMac