oh my god... im so sorry for troubling you like this, what a shame... i didn't realize the folder need to be set to 777. my mistake im sorry and thank you for helping me out.
i just couldn't understand before installing the plug in everyone can upload the picture without having any error. and after instal the plugin it turn out to be like that so i was thought that the plugin must have done something to it..
im sorry for troubling you thank you so muchhhhh...