A TimThumb error has occured

The following error(s) occured:

Could not find the internal image you specified.

Query String : src=/upload/resize_cache/iblock/fcf/800_600_1f88da2b4740de19584cdff1727090349/fcf2f9b246a48f3afe1737e2e819e29d.jpg&w=373&h=373&zc=2
TimThumb version : 2.8.11