diff --git a/certbot-nginx/certbot_nginx/configurator.py b/certbot-nginx/certbot_nginx/configurator.py
index d31a54c17..d526381a2 100644
--- a/certbot-nginx/certbot_nginx/configurator.py
+++ b/certbot-nginx/certbot_nginx/configurator.py
@@ -136,7 +136,9 @@ class NginxConfigurator(common.Installer):
         """
         # Verify Nginx is installed
         if not util.exe_exists(self.conf('ctl')):
-            raise errors.NoInstallationError
+            raise errors.NoInstallationError(
+                "Could not find a usable 'nginx' binary. Ensure nginx exists, "
+                "the binary is executable, and your PATH is set correctly.")
 
         # Make sure configuration is valid
         self.config_test()
diff --git a/certbot-nginx/certbot_nginx/parser.py b/certbot-nginx/certbot_nginx/parser.py
index a7ca2a735..a5cf2892e 100644
--- a/certbot-nginx/certbot_nginx/parser.py
+++ b/certbot-nginx/certbot_nginx/parser.py
@@ -222,7 +222,7 @@ class NginxParser(object):
                 return os.path.join(self.root, name)
 
         raise errors.NoInstallationError(
-            "Could not find configuration root")
+            "Could not find Nginx root configuration file (nginx.conf)")
 
     def filedump(self, ext='tmp', lazy=True):
         """Dumps parsed configurations into files.