I need to validate other fields on the page before the file is actually uploaded. The problem is I have no access to the event which occurs when the user starts the upload process. This appears to all be handled in your dll. I would like to receive and event when the user attempts to start the upload, validate some other data on the page (like an email address or name field for example), then proceed with the upload if the other data checks out. If not, the file will not be uploaded.