Kaltura_Client_Exception thrown

Invalid KS "MTVkNGVkN2M0NGIxNjQyZDRlN2I2ZDQwMWU2NDA5ZTU2ZTYyYTE0NHwxMDE7OzE0NzQ5MDU1MzE7MjsxNDc0ODE5MTMxLjgxMTtBbm9ueW1vdXM7ZWRpdDoq", Error "-1,INVALID_STR"