i:4;s:59:"gliffy-plugin-for-wordpress/gliffy-plugin-for-wordpress.php";

had to deactivate from the backend by removing this :

i:4;s:59:”gliffy-plugin-for-wordpress/gliffy-plugin-for-wordpress.php”;

http://ww.wp.xz.cn/extend/plugins/gliffy-plugin-for-wordpress/