Outlook 2011 client, Exchange 2010 server; letters missing in text of sent items

This question is old, but still appears on the first page of "unanswered," so I wanted to add a few points.

• it isn't clear if this is an issue with message content or rendering
• To determine which is the issue, in the folder's message list, command-click on the message and select "view source" from the context menu.
  • This will open the email as sent in textpad, from where you may be able to see if the content is correct.
  • If you cannot tell if non-printable characters are present, save a copy of the message source to a text file:
  • Choose File > Duplicate, choose File > Save, type a name, choose where you want to save the document, and then click Save.
  • In a terminal window run "od -tc my_mail_message.txt | less"
  • you'll probably see a confused mess of different line endings, with both 012 and 015 appearing individually.
• if it is a font issue, then viewing in plain text should resolve that. If it doesn't, it isn't a font issue, though it could mean that character is not printable in the default display font.