Error: "Excel encountered an error and had to remove some formatti
 

I have a workbook containing a lot of conditional formatting and option
boxes. It works fine on my PC using office 2000 but when opened on another PC
with office 2002 it gives the error message, "Excel encountered an error and
had to remove some formatting to avoid corrupting this workbook..." Both have
the same operating system (XP Professional). I changed out the worksheet
containing all the option boxes to no avail. Also, would this "formatting" it
is talking about be conditional or normal (protecting cells, etc.)? Thanks in
advance.