To add a favicon, you must create a tag and add it to WEBSITE SERVICES > TECHNICAL SETTINGS > META TAGS & WEBSITE PRELOADERS. The image file must be in .ico format and must be uploaded to your FILE LIBRARY in FILES & DOCUMENTS. The tag that you create should be in the following format:

<link rel="shortcut icon" href="/images/favicon.ico" />

Replace "myicon.ico" with your .ico filename.