Salesforce Developer Community

We recently purchased Crystal Reports to help with some of the reporting issues that we have had with Salesforce.

When I attempt to add the Activity History table/database to one of my Crystal Reports I get the following error:

"Database Connector Erro: "INVALID_TYPE_FOR_OPERATION: entity type does not support query"

This is the only section of salesforce that I get this for, I can access the Account table, Opportunity table, etc.

Any thoughts on what might be causing this error?