When you open a MIME email and it contains images from web sites, the images are not shown. Instead, images are displayed as a red box until you click the 'Show images' link:
The image whitelist feature alters this behavior. The image whitelist is a list of websites (host names such as www.ibm.com). If an image is stored in one of the websites in the list, the image is automatically shown without having to click the 'Show images'. Images which are not in the whitelist continue to display a red box until you click 'Show images'.
: This feature is turned off
by default. To enable this feature, add the Notes.ini variable EnableImageWhiteList=1
The white list is part of the mail policy which administrators can create, edit and delete:
In the above example, an email containing both an image stored on an IBM website and an image stored on the Amazon.com website would display as shown below: