Fortunately, in Eudora sending emails using no formatting and just text is ridiculously easy.
Send a Message in Plain Text in Eudora
To make sure an email you have composed in Eudora is sent in pure plain text format:
First, let's make sure Eudora does not send HTML-formatted emails automatically and without asking us.
- Select Tools | Options... from the menu.
- Go to the Styled Text category.
- Make sure Ask me each time is checked under When sending mail with styled text (HTML):.
Now, when composing a message:
- Do not use any of the tools found in the formatting toolbar while composing the message.
- Do not change the font or font size, for example, or insert graphic smileys or objects (attach files instead).
- Eudora will automatically send the message using plain text formatting only.
- If you have inadvertently used formatting (in your signature, for example), Eudora will ask you for the delivery format when you click Send.
- Choose Plain.
How could you possibly use formatting "inadvertently"? If you use italics in your signature, for example.

