Restricting a limited user from deleting a excel file, but he can fill up data & Save the workbook?

I have windows XP pro with one Administrator %26amp; one Limited user . In excel 2007 I have created a file in that, the users have to update their data. But while updating data they unknowingly deleting the file. If i restrict them from deleting by security option, limited user unable save the excel workbook. How I can restrict the user only to update %26amp; save the excel worksheet, by not deleting the excel file?Restricting a limited user from deleting a excel file, but he can fill up data %26amp; Save the workbook?
You will have to use a 3rd party software to do that. There are many out there on the web uunfortunatelynone of them are free