Artwork problems with iPod classic

i have an 80gb iPod video. i have been putting movies on there without any problems, but the problem i am having is i cannot get my cover to show up like i did previously. i go into the artwork folder and place it there and click add but whenever i go to put it on my iPod, it is not there. whenever i check it again in my information, it is not there. try to add it again, and nothing. any ideas?

got it worked out.