The _REPORT* system varaibles are not populated in runtime automatically. See http://www.berezniker.com/content/pages/visual-foxpro/vfp-90-report-features-runtime

>What would cause _reportpreview to get set to the empty string in a VFP app. I'm not setting it explicitly, so I'm not sure how it would get stepped on. However, I've got an app where it's empty all of a sudden and I get errors when printing (File does not exist on the DO (_reportpreview) with oReportContainer line). I should be able to set it before the previous line executes, but I'm wondering why it's suddenly blank? And wouldn't it seem like VFP should default to ReportPreview.App if the system var is empty?