I can't seem to upload wallpapers. Could you help me?

Ok, so first if this tanong was already asked just give me a link and ulat the tanong (I do have to point out I searched before asking). If not:
Ok so I've been in Fanpop for about a taon and this whole taon I haven't been able to post a wolpeyper ever!

I use Photoshop and when I save the wolpeyper I put it on maximum quality...Maybe I sound stupid but every time I mark the 1200x800 image as a wolpeyper it gets post over Photos.

Ok well I hope you got what I said. Thanks for any help/advice you can give me.