Symptoms: A log-in prompt is presented to the user upon uploading files and the site uses Windows Authentication. If the site is configured with Forms Authentication the upload will fail without error message.
Cause: RadAsyncUpload will not send an authentication cookie when the end-user
has Flash Installed.
Solution: Exclude the
Telerik.Web.UI.WebResource.axd handler from authentication:
Note: Anonymous authentication must be enabled on the site for this workaround to work. If AA is disabled, you must disable the RadAsyncUpload Flash module altogether by inserting this script right before the control definition on the page:
We're investigating the possibility to automatically send the authentication cookie.