IOS Newsletter component must be installed previously in order for this module to work. http://wiki.elxis.org/wiki/Ios_newsletter
Other possible problemsThis error message means that there is a problem with the directory or folder permissions.one more...Directory or Folders on the web server should have permission settings of 755.Please check the permissions for this folder and sub-folders. \administrator\components\com_newsletter\ And if you use the IOSN Module \modules\mod_iosn_subscribe\ If you continue to have problems, please visit the Elxis Wiki and/or Forum.