NERDTree appearing blank in specific folders

Question

So I have NERDTree set up, and it mostly works just fine. Generally speaking, when I open Vim somewhere, NERDTree does its usual thing and starts working. However, there are some very, very specific directories at which, upon opening Vim, NERDTree just goes blank, and there's nothing but a cursor at the upper-left corner of the screen and nothing else. I've tried recompiling YouCompleteMe, redownloading and reinstalling Vundle and redoing the :PluginInstall command, and nothing solves matters. I can't figure out how to fix the issue.

Answer 1

I figured it out. Just on a whim, I decided to go to the directory level where the problem was occurring and run:

find . -name "*.swp"

and sure enough, there was a file named:

./.NERD_tree_1.swp

I deleted this file and tried again, and lo and behold, it worked. Hopefully, this will help out other folks who are finding the same problem.