投稿時にWarning: file_put_contentというエラー

投稿時にエラーメッセージが表示されて投稿できません。原因がわからないのでアドバイスお願いします。

Warning: file_put_contents(/home/users/2/moo.jp-mococo/web/wp-content/uploads/2015/04/pchttp%3a%2f%2fthumbnail.image_.rakuten.co_.jp%2f%400_mall%2fauc-azzuro-%2fcabinet%2f02317293%2fimg57403930.jpg%3f_ex%3d300x300ampmhttp%3a%2f%2fthumbnail.image_.rakuten.co_.jp%2f%400_mall%2fauc-azzuro-%2fcabinet%2f02317293%2fimg5740393010.jpg%3f_ex%3d80x80) [function.file-put-contents]: failed to open stream: File name too long in /home/users/2/moo.jp-mococo/web/wp-content/plugins/auto-post-thumbnail/auto-post-thumbnail.php on line 359

Warning: file_put_contents(/home/users/2/moo.jp-mococo/web/wp-content/uploads/2015/04/pchttp%3a%2f%2fthumbnail.image_.rakuten.co_.jp%2f%400_mall%2fauc-azzuro-%2fcabinet%2f02317293%2fimg57403930.jpg%3f_ex%3d300x300ampmhttp%3a%2f%2fthumbnail.image_.rakuten.co_.jp%2f%400_mall%2fauc-azzuro-%2fcabinet%2f02317293%2fimg5740393010.jpg%3f_ex%3d80x80) [function.file-put-contents]: failed to open stream: File name too long in /home/users/2/moo.jp-mococo/web/wp-content/plugins/auto-post-thumbnail/auto-post-thumbnail.php on line 359

Warning: Cannot modify header information – headers already sent by (output started at /home/users/2/moo.jp-mococo/web/wp-content/plugins/auto-post-thumbnail/auto-post-thumbnail.php:359) in /home/users/2/moo.jp-mococo/web/wp-admin/post.php on line 233

Warning: Cannot modify header information – headers already sent by (output started at /home/users/2/moo.jp-mococo/web/wp-content/plugins/auto-post-thumbnail/auto-post-thumbnail.php:359) in /home/users/2/moo.jp-mococo/web/wp-includes/pluggable.php on line 1178