[Grim_]

Your tutorial is finding the word LOSER inside the word LOSER.

pawn Code:

public OnPlayerConnect(playerid)
{
   new name[MAX_PLAYER_NAME];
   GetPlayerName(playerid, name, MAX_PLAYER_NAME);
   if(!strfind(name, "LOSER", true))
   {
      SendClientMessage(playerid, 0x0000ff, "Name not allowed.");
      Kick(playerid);
   }
   return 1;
}