This article implies that the codes for communicating with Prospero may still be available: http://www.dailymail.co.uk/sciencetech/article-2034379/Quest

This article implies that the codes for communicating with Prospero may still be available: http://www.dailymail.co.uk/sciencetech/article-2034379/Quest-revive-space-relic-lost-1996--British-launched-satellite.html Also, this blog post from 2012 says they haven't given up: https://web.archive.org/web/20121026003633/http://blogs.ucl.ac.uk/prospero-satellite/2012/04/04/long-overdue-update/ I can't find anything more recent -- but doesn't seem entirely hopeless.