Change outgoing message encoding
Each time you send a message, Gmail automatically selects UTF-8 encoding for the language(s) in which you've composed your mail. Although UTF-8 is a standard encoding that's accepted by many email clients, it's possible that the recipient may not be able to properly view the message you've sent.
If your contacts are having trouble viewing messages you've sent them, you can choose not to use UTF-8 for outgoing mail.
Here's how to switch your encoding setting:
- Click the gear in the top right.
- Select Settings.
- Scroll down until you see the 'Outgoing message encoding:' section
- Select Avoid Unicode (UTF-8) encoding for outgoing messages.