Crystal Report Error Logon failed.Details:crdb_adoplus: Object Reference not set to an instance of an object

Error Description:

Logon failed. Details: crdb_adoplus : Object reference not set to an instance of an object. Error in File C:\DOCUME~1\XXX\LOCALS~1\Temp\XXXX {3309D862-8288-4B18-AEC2-FA3B78AA2BA3}.rpt

Solution:

Check the field explorer. Then select Database Expert. Make sure that the tables selected matches in the xxx.aspx file consists of properties Report datasource in CrystalReportSource control