It's quite possible for a virus to infect your computer through Outlook Express's preview pane. Turning this feature off is a good idea. Screening every e-mail for virus infestations at the server level can be done, too; the server I use runs a current and updated Norton Anti-virus scan three times a day. This doesn't mean something can't slip through, but it helps. From what I've seen, the current version of Norton Anti-virus seems to handle BadTrans very well. Currently, I believe there are three different "flavors" of BadTrans, and Norton, so far, has picked them all up without any problem.