When students returned to the University of Colorado at Boulder campus this month, some discovered that their e-mail software no longer worked properly. But that should not have come as a surprise because university officials had been reminding them for months that Boulder would make a major change in its e-mail systems to tighten security. Over the holiday break, the university changed its e-mail systems to require encrypted communications for transmitting messages between campus e-mail servers and client software used by individuals, such as Netscape Communicator and Outlook Express. Full Story