function checkuser(){
        if(document.userform.imie.value==""){
          window.alert("Podaj swoje imie.\n(Enter your name)")
          errfound = true;
        }
        else
        if(document.userform.nazwisko.value==""){
          window.alert("Podaj swoje nazwisko.\n(Enter your surname)")
          errfound = true;
        }
        else
        if(document.userform.email.value==""){
          window.alert("Podaj swój e-mail.\n(Enter your e-mail)")
          errfound = true;
        }
        else
        if(document.userform.adres.value==""){
          window.alert("Podaj swój adres.\n(Enter your adress)")
          errfound = true;
        }
        else
        if(document.userform.kod.value==""){
          window.alert("Podaj kod pocztowy.\n(Enter post code)")
          errfound = true;
        }
        else
        if(document.userform.miasto.value==""){
          window.alert("Podaj swoje miasto.\n(Enter your city)")
          errfound = true;
        }
        else
        if(document.userform.telefon.value==""){
          window.alert("Podaj swój telefon.\n(Enter your phone number)")
          errfound = true;
        }
        else
        if(document.userform.kod.value==""){
          window.alert("Podaj kod pocztowy.\n(Enter post code)")
          errfound = true;
        }
        else
        if(document.userform.password.value==""){
          window.alert("Podaj hasło.\n(Enter your password)")
          errfound = true;
        }
        else
        if(document.userform.password_repeat.value==""){
          window.alert("Powtórz hasło.\n(Repeat your password)")
          errfound = true;
        }
        
        else
          return;
        return !errfound;
      }