Drag and drop out of Xojo to O/S

I have a container control which I have the ability to drag and drop onto other container controls, however, if I drag the file out of the XOJO window to my desktop (windoze) xojo locks up totally, even if running in debug mode (i have to kill the process to exit it). Anyone any idea why this is Jamming Xojo?

in the dropobject event i am issuing

if obj.RawDataAvailable(“text”) =true then
do things
end if

This is working fine for dragging containers to containers.