help

function sendMsg(userId, username)
{
 $.post("http://www.roblox.com/My/NewMessage.aspx?RecipientID='.length",{
  subject   :   "AI | Group Invite",
  body   :   "Hello, " + username + "!\n\n I see you're interested in fighting. I am now here to invite you to Allied Infantry.\n Allied Infantry is a rapidly growing clan, with over 3,900 members. If you join AI and are active, I can assure that you will have much success.\n\n If you do decide to join, I suggest you get Merely's Group Enhancer for Google Chrome if you want to become active, it's such a great way to improve your time with us. Simply go to the Chrome Webstore, search for \"ROBLOX Group Enhancer by Merely\" and click the 'Add to Chrome' button and you will be notified every time something happens!\n\nhttp://www.roblox.com/Groups/Group.aspx?gid=715274\nThank you,\n- TLE High Command",
  recipientid  :   userId,
  cacheBuster  :   new Date().getTime()
 }).complete(function(){
  console.log('Sent message to ' + username + '.')
 })
}

function getPlayers()
{
 var ids = []
 var sel = $('#ctl00_cphRoblox_TabbedInfo_GamesTab_RunningGamesList_RunningGamesContainer');
 sel = $(sel).find('a')
 for(i=0;i<sel.length;i++) {
  if(sel[i].href.toLowerCase().substring(0,'http://www.roblox.com/User.aspx?id='.length) == 'http://www.roblox.com/User.aspx?id='.toLowerCase()) {
   ids.push(sel[i].href.substring('http://www.roblox.com/User.aspx?id='.length))
  }
 }
 return ids
}

function getUsernames()
{
 var ids = []
 var sel = $('#ctl00_cphRoblox_TabbedInfo_GamesTab_RunningGamesList_RunningGamesContainer');
 sel = $(sel).find('a')
 for(i=0;i<sel.length;i++) {
  if(sel[i].href.toLowerCase().substring(0,'http://www.roblox.com/User.aspx?id='.length) == 'http://www.roblox.com/User.aspx?id='.toLowerCase()) {
   ids.push(sel[i].title)
  }
 }
 return ids
}

var players = getPlayers()
var users = getUsernames()

var i=0;
function Loop()
{
 setTimeout(function () {
      sendMsg(players[i],users[i])
      i++;
      if (i < players.length) {
         Loop();
      } else {
  alert('Done!')
   }
   }, 10000)
}

Loop()

This is where the error log is
jquery-1.11.1.min.js:4 GET http://www.roblox.com/RobloxDefaultErrorPage.aspx?id=5ddf3746-b2fd-42e0-82e0-208c0d7c3c86&mode=&code=500 500 (Internal Server Error)jquery-1.11.1.min.js:4 sendjquery-1.11.1.min.js:4 m.extend.ajaxjquery-1.11.1.min.js:4 m.(anonymous function)VM7876:4 sendMsgVM7874:47 (anonymous function)