In pratica (nel form il campo file ha attributo name="miofile" e la cartella di upload è chiamata "pub"):

<%

Response.Expires=0
Response.Buffer = TRUE
Response.Clear
byteCount = Request.TotalBytes
RequestBin = Request.BinaryRead(byteCount)
Dim UploadRequest
Set UploadRequest = CreateObject("Scripting.Dictionary")
BuildUploadRequest RequestBin
contentType = UploadRequest.Item("miofile").Item("ContentType")
filepathname = UploadRequest.Item("miofile").Item("FileName")
filename = Right(filepathname,Len(filepathname)-InstrRev(filepathname,"\"))
value = UploadRequest.Item("miofile").Item("Value")

Set ScriptObject = Server.CreateObject("Scripting.FileSystemObject")

Set MyFile = ScriptObject.CreateTextFile(server.MapPath("\pub") & "\" & filename)

For i = 1 to LenB(value)
MyFile.Write chr(AscB(MidB(value,i,1)))
Next

MyFile.Close

%>

Dove e come dovrei inserire la funzioncina?
Grazie