i found what causes it: when you try to add puppil by manual adding, if you put a "space" at the end of pupil's name it gives you this error.
Also i have another question about pupil commander: i registred a site that sustains me with working proxys and i use this proxies with "elite proxy switcher" and all works. The problem is when i try to work it with pupil commander it never gives an XP pupil. But exact opposite of this when i try to make pupil by mannually, it gives XP pupil almost all the time. Do you have any cause you can project ? if u enlight me about it, ill be very appriciated thanks