Crystal report show the blank page in c#.net

Hi , I m working in c# Visual Studio 2008 windows application . when i run the project first time crystal report show the blank page after that i pressed refresh button , report will display.i tried all report refresh concept but not working.

can u anyone plz tell me the solution for this...

Coding

Report_AMCDataPreview report1 = new Report_AMCDataPreview();
report1.SetDataSource(dd.Tables[0]);
report1.SetDatabaseLogon("Admin", "jts100");
crystalReportViewer1.ReportSource = null;
crystalReportViewer1.ReportSource = report1;

thanks & regards