Ihe OpenOpenPage-Trigger is called twice when a report is started in preview mode.

If a report has an request page with the propety SaveValues activated and the report has a printout like RDLC, than the OnOpenPage-trigger is called twice in preview mode. First time when start the report (which is correct) and the second time after push the preview button (which is wrong). If the OnOpenPage-Trigger initialize for example report parameters, than the second run potencially overwrites the user input from request page. So the user input is lost and the report every times started with wrong parameters in Preview Mode.

Preview Mode and normal Printing should behave similar!

Maybe the problem triggered by report child processed that the request page is not closed when start a SaveValues-Report in preview mode.

Some BaseApp-reports should have the same problem (for example the report 1301 will definitely have the same problem).

Check also MS Support TrackingID#2401310050002945