Martin -

I have an object named "oform". If I use set report "SET REPORTBEHAVIOR 90" oform's properties has been released. If I don't use "SET REPORTBEHAVIOR 90" it works normally...

You have probably indentified a place where the ReportPreview.App source code is using a variable oForm without first declaring it LOCAL. I will save you the time and tell you that there are two places where this is the case:

frxPreviewProxy.GetWindowRef()
frxPreviewToolbar.ActionZoomLevel()

I have not verified that this is the cause of your problem..

Perhaps this oversight will be addressed in VFP9 SP1, if there is one. In the meantime, if you can not change your source to avoid the oForm, you may try changing the ReportPreview.App source and recompiling that.

Regards,
- Colin