File size doesn't matter, the behavior is consistent regardless: No Request Files! appears after clicking a link to the page, or being redirected via asp.net.
---------------------------
Windows Internet Explorer
---------------------------
Server side exception : failed to upload 130_Castle Project License.txt
Debug Information:
System.Exception: No Request Files!
at CuteWebUI.UploadModule.a(HttpContext A_0, Guid A_1)
---------------------------
OK
---------------------------