diff --git a/README.md b/README.md
index 7da3d7f..8dd7d64 100644
--- a/README.md
+++ b/README.md
@@ -91,6 +91,14 @@ it, these are the steps:
         mv nginx.conf nginx.conf.bak  # backup the configuration file.
         ln -s ~/Projects/markdown-renderer/src/github.com/wangkuiyi/markdown-renderer/nginx.conf
 
+  1. (Optional) Edit `nginx.conf` to specify the document root
+     directory to be where Markdown Renderer source code is.
+
+        location / {
+            root   /Users/wangyi/Projects/markdown-renderer/src/github.com/wangkuiyi/markdown-renderer;
+        }
+
+
   1. Start Nginx.
 
         /usr/local/nginx/sbin/nginx
@@ -102,3 +110,7 @@ it, these are the steps:
         ~/Projects/markdown-renderer/bin/markdown-renderer
 
 
+### Trouble Shooting
+
+Markdown Renderer requires that the Markdown filename matches the
+regular expression `^/([_a-zA-Z0-9]+)\\.md$)`.
diff --git a/nginx.conf b/nginx.conf
index eaaa954..ec46a71 100644
--- a/nginx.conf
+++ b/nginx.conf
@@ -10,8 +10,8 @@ http {
         server_name  localhost;
 
         location / {
-            root   /Users/wangyi/site;
-            index  index.md;
+            root   /Users/wangyi/Projects/markdown-renderer/src/github.com/wangkuiyi/markdown-renderer;
+            index  README.md;
         }
         location ~ \.md$ {
             proxy_pass http://localhost:8002; # Markdown Renderer server.
@@ -23,7 +23,7 @@ http {
         server_name  localhost;      # Markdown source loader server.
 
         location / {
-            root   /Users/wangyi/site;
+            root   /Users/wangyi/Projects/markdown-renderer/src/github.com/wangkuiyi/markdown-renderer;
         }
     }
 }