It will send you packing, Worse still you may have a "circular reference" and you will get a lecture.

BBC: The mysterious powers of Microsoft Excel

It is understood that all e-mail users must observe the standards governing the use of those technologies and facilitate optimum network administration (reference: the Administrative Circular No. 2204 of 22 March 2004: Directives for the Use of Information and Communication Technologies in UNESCO).

UNESCO: Website Toolkit