We got this message from our IT dept.:
Computer Virus Issue
Many reports are coming in from around the world that a new technique is being used in an attempt to defeat virus protection systems. If you receive a message that looks like the following:
Dear user of "123.com" (or whatever your email domain may be. i.e. comcast.com) mailing system,
Our main mailing server will be temporary unavailable for next two days, to continue receiving mail in these days you have to configure our free auto-forwarding service.
Or,
if you get an email message with a .zip attachment protected by password, don't try to open the attachment!
Delete any message that meets these criteria. Do not attempt to open any password-protected files with a .zip extension UNLESS you are specifically expecting a .zip file WITH a password from that particular person.