Managed finally to get it to work
Add a handler for the UploadedComplete event
AddHandler AsyncFileUpload1.UploadedComplete, AddressOf FileUploaded
Capture the bytes in the event
Private Sub FileUploaded(ByVal sender As Object, ByVal e As AjaxControlToolkit.AsyncFileUploadEventArgs)
Try
If AsyncFileUpload1.HasFile Then
Session("UploadedPDF") = AsyncFileUpload1.FileBytes
End If
Catch ex As Exception
EmailError(ex.ToString, "25")
End Try
End Sub
Upload the file to the DB if it is there
If Not Session("UploadedPDF") Is Nothing Then
vCmd.Parameters.AddWithValue("@Update_Document", Session("UploadedPDF"))
End If