Ok erenda, it should work now. It happened sometimes that the temprary image that you uploaded in the temporary folder remains stuck there...
I think it happens because you're trying to upload during some server manteinance. Posetteforever is located on a server in the U.S.A. so they do the manteinance while the people there are supposed to sleep, but not us here... lol..
A temporary solution should be to wait a little (about half a hour), inform me (I've to delete the pictures manually so I'm the only one who can do it) and in any case try to upload the same image renaming it...
Try now and say me if it works, it should