pb 10.5 rtf datawindow insertdocument function crashes in vista m/c

pplication : Powerbuilder 10.5 Build 4523

RTF insert document function is used to insert rtf data into RichTextEdit Datawindow.

dw_1 is  RichtextEdit Datawindow

rte_1 Richtext Edit control

dw_1.Object.DataWindow.RichText.DisplayOnly = false 
rte_1.SaveDocument(ls_docname, FileTypeRichText!)  
dw_1.accepttext() 
dw_1.selecttextall() 
dw_1.clear() 
dw_1.insertdocument(ls_docname, false, FileTypeRichText!)  
dw_1.ShowHeadFoot(true,false) 
dw_1.retrieve(il_patienttestno) 
dw_1.ShowHeadFoot(false,false) 
dw_1.Object.DataWindow.RichText.DisplayOnly = TRUE 

Application works fine in Windows XP but crashes only in Windows Vista & Windows 7 PC.Is there any workaround or suggestions to overcome issue?

The issue is that data is retireved properly in richtext edit style datawindow but later on clicking on datawindow application hangs.