Turn off automatic message encoding

If you are using Microsoft Internet Explorer 5.5 or later, Microsoft Outlook automatically evaluates the text in a message and selects the encoding (character sets) used to display all characters in the message.

1. On the Tools menu, click Options.
2. Click the Mail Format tab, and then click International Options.
3. Under Encoding Options, clear the Auto-Select encoding for outgoing messages check box.

Note  To turn on automatic message encoding, select the Auto-Select encoding for outgoing messages check box.