Here's another idea:
"You can still display the formulas of locked cells in the formula bar, as long
as you did not select the Hidden option when you protected them. You can
recover your formulas and data by copying them to a new sheet. If you have
hidden any cells, Excel copies the returned values rather than the formulas. Be
very careful when password-protecting hidden cells. Make sure you type the
password in accurately when you protect the sheet, and write the password down
and put it in a safe place." Excel Professional Techniques, published by Que.
My "bible" for Excel. 781 pages of great information.
Good luck. Let us know if you got your data back.