Word attachment file name prints as icon with ? inside when I print email I have a Mac with Word 2011.  Every now and then when I print an email with a Word attachment, my HP printer prints an icon with a question mark instead of the Word file name.
Same problem here with a MacPro Yosemite and an old hp printer. At least you can get it to display properly in your and the recipient's computer though not to print properly. 

Go to Mail Preferences - Accounts - Advanced and uncheck "automatically detect and maintain mail settings"