The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).

I keep getting this error on one of my pages but the only code blocks on the page are:

<%@ Page Language="VB" MasterPageFile="~/MasterPage.master" AutoEventWireup="false" CodeFile="UserAdministration.aspx.vb" Inherits="Administrator_UserAdministration" title Go to the complete details ...