Excel 2000 and earlier allocated 100 MB of RAM for its full pivot table workspace. Excel XP uses strategies to make more available, but Microsoft documentation is unclear how much. By querying more than that, regardless of what is being displayed in the pivot table, the user runs out of available memory. The limit can be exceeded by refreshing data that has grown to more than 100MB in the course of time, even if the original report was created with less.
Strategies for dealing with this situation:
1. If possible, re-build the report from scratch with fewer fields included in the query, or use filtering to reduce the total number of records queried.
2. Use MSQuery (chapter 6 in the user manual) to reduce the number of fields queried in the existing report.
3. Get Office XP. The same report can be opened and ""upgraded"" within XP, without generating it anew.