Hola, porque no pruebas de esta forma :
Código:
Dim MiReporte as new CrystalReport1
Dim crTables As CrystalDecisions.CrystalReports.Engine.Tables
Dim crTable As CrystalDecisions.CrystalReports.Engine.Table
Dim crConnInfo As New CrystalDecisions.Shared.ConnectionInfo
Dim crLogOnInfo As CrystalDecisions.Shared.TableLogOnInfo
crTables = MiReporte.Database.Tables
For Each crTable In crTables
crConnInfo.DatabaseName = "localhost"
crConnInfo.ServerName = "clientes"
crConnInfo.UserID = "sa"
crConnInfo.Password = "masterkey"
crLogOnInfo = crTable.LogOnInfo
crLogOnInfo.ConnectionInfo = crConnInfo
crTable.ApplyLogOnInfo(crLogOnInfo)
Next
CrystalReportViewer1.ReportSource = MiReporte
Saludos
