John Simek, a computer forensic examiner in Fairfax, Va., recently had a woman come to his office after a divorce proceeding. In court, her husband had presented some mean-spirited e-mails she supposedly sent him from a free Hotmail e-mail account, which led the judge to award the husband sole custody of their children. The woman claimed she’d never seen these messages before, and because the man only presented printouts of the alleged e-mails, Simek knew there was a chance they were fakes…