At a certain level, it is in fact acceptable to miss the occasional e-mail. Yes, there’s a chance that your spam filter will nuke from orbit or exile to Coventry an e-mail which is actually legitimate, but there’s also a chance that your cat will jump on the keyboard and accidentally hit the “delete” button, or that your ISP’s mail server and backups both get hosed, or that the system works fine technically but you just happen to overlook an e-mail. In all these cases, life goes on. The only time I ever actually look at my spam folder is when I know specifically that I should have gotten an e-mail, but haven’t (an Amazon order confirmation, say), and on those occasions, I only have to see a page or so of penis enlargement offers, since I know that the mail I’m looking for was in the past day (and in fact, usually the past five minutes).