Hi LX,
Sorry for the inconvenience caused. We have tested this issue on our side and we can easily open the PageSetup dialog. Please refer to the attached video file that shows our test result.
http://www.syncfusion.com/Support/user/uploads/Diagram_6cd96215.zipCould you please try printing a document involving non syncfusion control and let us know if you face the same error.
Thanks for using Syncfusion product.
Thanks,
Nagaraj