fixed a series of "next" and "previous" topic links that pointed to the wrong pages.
diff --git a/user_guide/installation/troubleshooting.html b/user_guide/installation/troubleshooting.html
index 27c9c48..62c7548 100644
--- a/user_guide/installation/troubleshooting.html
+++ b/user_guide/installation/troubleshooting.html
@@ -77,7 +77,7 @@
<div id="footer">
<p>
-Previous Topic: <a href="upgrading.html">Upgrading Instructions</a>
+Previous Topic: <a href="upgrading.html">Upgrading from a Previous Version</a>
·
<a href="#top">Top of Page</a> ·
<a href="../index.html">User Guide Home</a> ·