I have a custom control with one file upload control. This page also has a couple fields that use partial refresh for various events (none of which refresh the upload control or a panel that contains the control). If a user selects a file and saves the page, all is fine. However, if they select a file and then use one of the fields that perform a partial refresh, then the file gets submitted to the server AGAIN and now when the page is saved and reopened, we see two files attached, file and file-2. We are seeing instances where a user selects a file, then selects a few different options on the page, which is resubmitting the file attachment each time and now when the document is reopened, the download control shows 20 files!!! file, file-2, file-3, file-4, etc.
What do I need to do to stop the resubmitting of the file attachment?