Pivot Calculated Field

I'm trying to insert a calculated field in my pivot table and I'm getting a
"there are too many records to complete this operation" error. I have about
10,000 records in the data sheet. Has anyone encountered this? Is there a
way around it?

I just encountered this problem yesterday.
The only thing that I was able to identify as a problem was that the pivot table was created with Office XP, and didn't seem to work under Office 2003. Running the same operation on a machine that hadn't yet been upgraded to 2003 worked fine.