fileupoad control not giving the path in firefox

i am using file upload control
if  i check tha applicaion in IE i get it correctly
i slect a file using fileuplaod control and use fileuplad.postedfile.filename
so i get teh physical path of the file
whereas from firefox i just get the filename not the path hence i am not able to get teh file
as its showing me msg unable to load file
i need to get the physical path of the file
i cant use server.mappath as the file can be from any drive
how can i get the filename with path
 
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