Pivot Tables - "problems obtaining data"

I've been using the Create Pivot Table Form wizard in
Access 2000 for some time with no problems at all.
Suddenly I'm finding that it no longer works and returns a
message saying that there are "problems obtaining data".
This is happening in any database I try it with. If I try
the same thing on another PC on our network it works fine -
so the problem is obviously related to my PC rather than
a specific database.

I suspect that maybe a required file has got corrupted (on
the day that the problem first arose I received
some "virtual memory low" messages, so maybe that's
related). I've tried reinstalling Office 2000 but the
problem persists.

I know I can still create the pivot table by exporting to
Exel and doing it manually, but that would be a lot of
hassle as i have to create a lot of these things very
regularly! Can anyone help? (I'm running Windows 2000).