I moved all the email to temporary folders. Logged out of Outlook Express, deleted the Inbox. Logged back in Outlook Express, and it created a new Inbox free of virus. The I start sorting my emails, until I found the one the set off the alarm, deleted it, moved the email back to the Inbox, deleted the temporary folders, and Avast no longer detected any virus. The email message had no attachment, and was created using an Outlook Express Template.