Input=file problem

Hi

I have been writing a program to automate some common web sessions i do for my work.

Ie logon, download info etc. i can get this all to work except on one form where i want to upload files from my computer, the element is Input = file. I cannot programically write a value to it. I have tried:

writing to its outerHTML atribute

changeing its type to text

and many other variations

I am pulling my hair out here, every thing else in my program works automatically but i have to wait for this section then manully upload the file.

Any ideas