When a document with a filename containing either an ampersand or an asterisk character in it arrives attached to an email, the characters disappear from the filename when you open the attachment.
An Outlook user had this to say: "When you first open the e-mail and see the attachment, the filename looks fine and has all its characters. However, when you open the document, the '&' and the '*' are removed. Even if you do a 'Save as' the characters are still missing."
In the case of the asterisk (*), it's because it's not a valid filename character in Windows, Asterisks will always be removed when you open or save an attachment containing this character.
Outlook removes the ampersand (&) if you open the attachment from the message. If you save the file using Save as (or Save All Attachments) from the message, the filename should retain the ampersand. Open the saved attachment from Windows Explorer to retain the & in the filename.
Published August 25, 2011. Last updated on September 16, 2013.