Not Sure of Origin? Don't Open
Most viruses spread by using email - and nearly all of the viruses
spread this way are hidden in an email 'attachment'; a small file like a
Word document or picture that is attached to an email message.
So, if you receive an email with an attachment from somebody you don't
know - don't open it.
In particular, look out for the following types of attachments, as
viruses are often hidden inside them