If you see the MIME Save Warning dialog box, it means you are sending an email that uses Multipurpose Internet Mail Extensions (MIME) to display the formatting. You are receiving the warning because there are some features in Notes that cannot be expressed in MIME, such as hotspots and horizontal rules, so those features may not work or they may disappear when you send or save that email.

If the message you are sending contains more than one language's character set, you may also see the Multilingual MIME Warning dialog box. You can select either Unicode or the best native character set to handle the content of the document.