pls help me how to upload and convert stl to dwg file

Please go to the page:
http://www.cadforum.cz/catalog_en/stl2dwg.asp
 
select your local STL file and choose the target (converted) file format for download. Both SCR and DXF files can be then opened in AutoCAD and saved to a DWG file.

not ok, but if click convert it will ask for first upload to finish(showing error msg)Pls help me.

ok thank you so much