Tom,

Thanks for the reply.

I should have given more information here, as your suggestion was the
first thing I tried to do.

When you ask Excel to track changes, you have the option to display all
changes made to the spreadsheet in a separate sheet that Excel tacks on
the end of your spreadsheet. That sheet is labeled "History", and it
provides a history of changes to your spreadsheet in a table with the
column headings "Action", "Date", "Time", "Who", "Change", "Sheet",
"Range", "Old Value", "New Value", etc. The sheet cannot be
unprotected (I've tried to do that), and so the number format cannot be
changed, and that's what my problem is... In a sheet created
entirely by Excel itself, how and WHY would it create columns called
"Date" and "Time" and 1) display the data in a number format that
renders them pretty much useless, and then 2) lock the format so as to
give you no way to fix it???

Rory