title: NERDTree: Autocmd error vim
body: <p>I am trying to add NERDTree to my RHEL machine by appending following lines in .vimrc after placing NERD_tree.vim in plugin folder.</p>
  
  <pre><code>autocmd VimEnter * NERDTree
  autocmd VimEnter * wincmd p
  </code></pre>
  
  <p>The problem is that I am able to run it using these commands in Mac but RHEL throws this error:</p>
  
  <pre><code>Error detected while processing VimEnter Auto commands for "*":
  E492: Not an editor command: NERDTree
  </code></pre>
  
  <p>Can somebody help me resolve this error?</p>