Duplicate contents when exporting to PDF from CR Viewer.

Hello,

I'm using VB.NET 2008 and crystal reports basic that comes with VS2008, when the report is exported to pdf using Export option from Crystal Report Viewer, when pdf is opened it appers with duplicates of the sheet , sometimes it duplicates 2 times or 3 times, it's only when pdf is opened when the report is viewed from CRViewer it appear correctly, only happens on end user computers, in developer computer all is OK.
Do I need to configure something special, any suggestions?

Thanks.

Roberto Ayala
Monterrey MX