Code:
on *:TEXT:-tanklin register *:?: {
  if ($isfile(tanklinplayers.ini) == $false) { write -c tanklinplayers.ini }
  if ($readini(tanklinplayers.ini,players,$nick)) {
    msg $nick 0,1[14««7« 0You already registered ! 7»14»»0]
    halt
  }
  var %inicount = $ini(tanklinplayers.ini,players,0)
  if (%inicount <= %tanklinplayers) {
    if ($readini(tanklinplayers.ini,players,$nick) == $null) {
      writeini tanklinplayers.ini players $nick $3
      msg $nick 0,1[14««7« 7R0egistration 7S0uccessful ! 7U0ser:7 $nick 7P0assword:7 $3 7»14»»0]
    }
  }

  if (%inicount > %tanklinplayers) {
    msg $nick 0,1[14««7« 0Sorry, the tournament is full ! 7»14»»0]
  }
}
on *:TEXT:-list:#: {
  var %inicount = $ini(tanklinplayers.ini,players,0)
  var %i = 1, %users
  while (%i <= %inicount) {
    var %users = %users $ini(tanklinplayers.ini,players,%i)
    inc %i
  }
  msg $chan Current Players: %users
}
on *:TEXT:-tanklin unregister *:?: {
  var %checkID = $readini(tanklinplayers.ini,players,$nick)
  if (%checkID == $3) {
    remini tanklinplayers.ini players $nick
    msg $nick Your Nick $+(",$nick,") has been removed from the players list.
  }
  else { 
    msg $nick 04,01 ERROR! Your password does not match entry for $nick $+ ! Unregister denied!
  }
}

try that