Reply flags for the message. These flags can be set as follows:
DMFL_NATIVERENDER
The source does not support rendering
for this object. A source should not set this flag unless it provides sufficient
information at the time of the drop for the target to perform the rendering
operation. The target must send DM_ENDCONVERSATION to the source after carrying
out the rendering operation or when it elects not to do a native rendering.
DMFL_RENDERRETRY
The source
supports rendering for the object but does not support the selected rendering
mechanism and format. The target can try another mechanism and format by
sending another DM_RENDER message. If the target does not retry, it must
send a DM_RENDERCOMPLETE message to the source. This flag is set in conjunction
with the DMFL_NATIVERENDER flag.