While uploading images we are receiving “Not a valid image” error message. To resolve error message refer following steps.
First login into Joomla admin section and check box following option.
Global Config > System
– restrict uploads = No
– check mime types = No
Second edit configuration.php file and change.
From
var $ftp_enable = ’1?;
To
var $ftp_enable = ’0?;
Third comment following line in php.ini file if you are using customize php.ini file (mostly used on SuExec server).
;upload_tmp_dir = tmp
And now try to upload the image.