A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Read the article at the link given below.
The article says - The product of the number of items in all column fields in a PivotTable cannot exceed 32,768.
I am not sure whether this limit is also linked to the Excel version ( I mean different for Excel 2007, Excel 2010 , and so on).
Check what is your count ? Is it within the permisible limit ?
https://support.microsoft.com/en-us/kb/211517#/en-us/kb/211517
Hope this is Helpful.