diff --git a/flake8/hooks.py b/flake8/hooks.py
index 2d1db8d..c25b9aa 100644
--- a/flake8/hooks.py
+++ b/flake8/hooks.py
@@ -155,14 +155,20 @@ def _get_files(repo, **kwargs):
 
 
 def find_vcs():
-    _, git_dir, _ = run('git rev-parse --git-dir')
-    if git_dir and os.path.isdir(git_dir[0]):
-        if not os.path.isdir(os.path.join(git_dir[0], 'hooks')):
-            os.mkdir(os.path.join(git_dir[0], 'hooks'))
-        return os.path.join(git_dir[0], 'hooks', 'pre-commit')
-    _, hg_dir, _ = run('hg root')
-    if hg_dir and os.path.isdir(hg_dir[0]):
-        return os.path.join(hg_dir[0], '.hg', 'hgrc')
+    try:
+        _, git_dir, _ = run('git rev-parse --git-dir')
+        if git_dir and os.path.isdir(git_dir[0]):
+            if not os.path.isdir(os.path.join(git_dir[0], 'hooks')):
+                os.mkdir(os.path.join(git_dir[0], 'hooks'))
+            return os.path.join(git_dir[0], 'hooks', 'pre-commit')
+    except OSError:
+        pass
+    try:
+        _, hg_dir, _ = run('hg root')
+        if hg_dir and os.path.isdir(hg_dir[0]):
+            return os.path.join(hg_dir[0], '.hg', 'hgrc')
+    except OSError:
+        pass
     return ''
 
 
@@ -269,7 +275,7 @@ def install_hook():
         p = get_parser()[0]
         sys.stderr.write('Error: could not find either a git or mercurial '
                          'directory. Please re-run this in a proper '
-                         'repository.')
+                         'repository.\n')
         p.print_help()
         sys.exit(1)