ODBC (Excel) connection string not working in report server

Hi:

In SSRS 2008 R2, i am developing the report using Excel 2010. For that am using ODBC connection type. when i run the report in BIDS it's running fine, but when i run it in report server it's throw an error as below.

• An error has occurred during report processing. (rsProcessingAborted)
  • Cannot create a connection to data source 'Conn_Excel'. (rsErrorOpeningConnection)
    • ERROR [IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified

Thanks in advance

Paramesh G