This can happen when sending or receiving email with characters that are not supported by the recipients installed character set. 


The sender can try setting one, or both, of the following options and then resend the email:


Change encoding to UTF-8

  1. Open Outlook and click the File menu.
  2. Click Options, and then click Advanced.
  3. Scroll down to International Options, and then change Preferred encoding for outgoing messages to Unicode (UTF-8).
  4. Click OK.

Disable smart quotes


  1. Open Outlook and click the File menu.
  2. Click the Mail tab, and then click Editor Options.
  3. Click AutoCorrect Options, and then do the following:
    1. In the AutoFomat As You Type tab, clear the "Straight quotes" with "smart quotes" check box.
    2. In the AutoFormat tab, and under Replace, clear the "Straight quotes" with "smart quotes" check box.
  4. Click OK.