Logon failed error

Hi All,

I use CR 11.5 to build report, datasource is ttx.
In VB.NET, I use ActiveX Crystal Report viewer to view the report.

This report (and subreports), only link to same single table.
I pass in the Dataset to main and subreport using SetDateSource().

1) When I preview the report, I got the error 'Logon Failed'.
If I pass DataTable to main report, and DataSet to subreport, no error will occur.

Do you have any idea?
Actually my report don't need to login to any database.

2) Another error about accessing protected memory will popup quite frequently. If I continue to preview for few more times, it suddenly will work!!!!! Do you know what's wrong?

Thanks!!!!