After reading the post you linked, it is clear;y written, "If Ajax Uploader detects SilverLight is installed on your PC, It will use the SilverLight solution". This is exactly what I want, to use Silverlight (uploading large files). With silverlight installed, I get a message "Please install silverlight v3 or higher", and it is installed. I think my problem is related to using the component in a IFRAME element. But it is a bit silly that a component wouldnt work because of that.

 

Rafael