When I visit the RadAsyncUpload demo (http://demos.telerik.com/aspnet-ajax/upload/examples/async/multiplefileselection/defaultcs.aspx?product=asyncupload) in IE9, with Flash, but not Silverlight installed, it only allows me to select one file at a time.
Turning on Silverlight, I can select multiple files.
Switching Browser Mode in IE to IE8 allows me to select multiple files.
But IE9 is single select only.
I'm running Windows 7 Pro, with Flash version 11.4.402.278, which is currently the most recent version. I don't have any other add-ons installed, and all settings are the base install settings for IE.
All the upload documentation says that multiselect is available if Flash is installed, but I'm not seeing that behavior.