On vundle\'s homepage, it documented that it requires filetype to be off in .vimrc:
filetype off \" required!
set rtp+=~/.vim/bundle/vund
I wanted to address the why part of this problem.
Most of this answer is from the following github thread
https://github.com/VundleVim/Vundle.vim/issues/176
It is Vim's feature.
Vim makes cache for filetype plugins from runtimepath. So if vundle changes runtimepath, it must reset before calling.
It's also said there that this problem was only there before 7.3.430.
As @Maxim Kim has answered, its better to turn it on after everything related to Vundle
set nocompatible
filetype off
set rtp+=~/.vim/bundle/Vundle.vim
call vundle#begin()
" Let vundle manage itself:
Plugin 'VundleVim/Vundle.vim'
" Syntax checking plugin
Plugin 'scrooloose/syntastic'
call vundle#end()
filetype plugin indent on " Filetype auto-detection
syntax on " Syntax highlighting