you're probably running bsetbg as a different user to the one who started the X server. make sure you are the same person, i'd guess you might be running that as root?
That's true. I was root and when I'm that person that started X server there is no problem. The problem is now that when I give that command the wallpaper doesn't change neither Konsole give any errors. How I can set background if bsetbg doesn't work?