Pivot table error
 

I recently starting using Excel 2000 and keep getting the following error
message when adding new fields to the Row section of the table:

"Excel cannot make this change because there are too many row or column
items. Drag at least one row or column field off the pivot table or the page
position..."

It will allow me to use up to 4 fields in the Row, but not more than 4. I
am able to create the same table in Excel 97 without any problems. My table
is only 500 rows high, so it's well within the limits, but I still get the
error.

Any thoughts?