TimThumb Error

The following error(s) occurred:

• You may not fetch images from that site. To enable this site in timthumb, you can either add it to $ALLOWED_SITES and set ALLOW_EXTERNAL=true. Or you can set ALLOW_ALL_EXTERNAL_SITES=true, depending on your security needs.

Query String: src=https%3A%2F%2Figcdn-photos-f-a.akamaihd.net%2Fhphotos-ak-xap1%2Ft51.2885-15%2Fe15%2F10448987_1696648753915541_1172131675_n.jpg%3Fig_cache_key%3DMTIwMzU0MDA1ODIzNzkzNzUyMw%3D%3D.2&w=90&h=64&zc=1
TimThumb version: 2.8.14
Instruction: Thumbnails don't work — what to do? (registration required)