Error message: "Index 0 is out of range, Parameter name:index"

Dear Friends,
Please could someone help me on this.
I have a button on which when clicked will display the crystal report.
This report displays results as required, but when I want to view the report second time,
there's this error message: "Index 0 is out of range, Parameter name:index".
The user just selects the date from the DateTime Picker control and clicks the OK button and the report should be display. The report is generated from a view in SQL Server 2005 Database.

Thanks & Regards,
Aamir