The Icons page allows Admins to change the icon images for all attendees, sessions, exhibitors, and meetings. Typically these are generic images. Attendees that change their profile picture will overlap these images as their profile changes overwrite any changes made in admin.
To change these images, go to Admin>Appearance>Icons. Admins will come to this page:
Simply click Change Icon and click on the camera image to browse for the image through the computer. If the image is being hosted from an external source, Admins can supply a URL as well. Image sizes should be a square image and for the best results should be a 300x300 image.