Thumbnail generation unsuccessful

• DEBUG post_id=1798
• DEBUG Found YAPB image
• DEBUG w=180
• ERROR Couldn't save /usr/www/virtual/uofcomba/www.chobesafari.com/wp-content/uploads/yapb_cache/damnpotholes1.c10w6qqpp1c0s8ow0wckwg8o4.a9sxxja1njksswcs400wcc4cg.th.jpeg - Please check cache directory permissions