some user guide corrections in code examples
a minor grammar tweak
diff --git a/user_guide/toc.html b/user_guide/toc.html
index 288bbc5..ddd249b 100644
--- a/user_guide/toc.html
+++ b/user_guide/toc.html
@@ -74,7 +74,7 @@
 <ul>
 	<li><a href="./installation/downloads.html">Downloading CodeIgniter </a></li>
 	<li><a href="./installation/index.html">Installation Instructions</a></li>
-	<li><a href="./installation/upgrading.html">Upgrading from an Previous Version</a></li>
+	<li><a href="./installation/upgrading.html">Upgrading from a Previous Version</a></li>
 	<li><a href="./installation/troubleshooting.html">Troubleshooting</a></li>
 </ul>