diff --git a/html/inc/forum.inc b/html/inc/forum.inc
index f850901338..88792e4154 100644
--- a/html/inc/forum.inc
+++ b/html/inc/forum.inc
@@ -515,10 +515,6 @@ function show_post(
     global $country_to_iso3166_2;
 
     $user = BoincUser::lookup_id($post->user);
-    BoincForumPrefs::lookup($user);
-    if (is_banished($user) && !is_moderator($logged_in_user, $forum)) {
-        return;
-    }
 
     // If the user no longer exists, skip the post
     //
@@ -527,6 +523,11 @@ function show_post(
     }
 
     $config = get_config();
+    BoincForumPrefs::lookup($user);
+    if (is_banished($user) && !is_moderator($logged_in_user, $forum)) {
+        return;
+    }
+
     $no_forum_rating = parse_bool($config, "no_forum_rating");
 
     $tokens = "";
@@ -754,6 +755,11 @@ function show_post_and_context($post, $thread, $forum, $options, $n) {
     $content = output_transform($post->content, $options);
     $when = time_diff_str($post->timestamp, time());
     $user = BoincUser::lookup_id($post->user);
+    if (!$user){
+        return;
+    }
+
+    $config = get_config();
     $title = cleanup_title($thread->title);
     if ($post->hidden) {
         $deleted = "<br><font color=red>[".tra("Hidden by a moderator")."]</font>";
@@ -1322,6 +1328,7 @@ function show_thread_and_context($thread, $user) {
     if (!$thread_forum) return;
     if (!is_forum_visible_to_user($thread_forum, $user)) return;
     $owner = BoincUser::lookup_id($thread->owner);
+    if (!$owner) return;
     echo "<tr><td>\n";
     switch($thread_forum->parent_type) {
     case 0:
diff --git a/html/inc/text_transform.inc b/html/inc/text_transform.inc
index 8df556efc0..d5d5f31621 100644
--- a/html/inc/text_transform.inc
+++ b/html/inc/text_transform.inc
@@ -68,7 +68,7 @@ function output_transform($text, $options = NULL) {
         $options = new output_options; // Defaults in the class definition
     }
     if ($options->htmlitems) {
-        $text = htmlspecialchars($text);
+        $text = htmlspecialchars($text, ENT_COMPAT | ENT_HTML401 | ENT_SUBSTITUTE);
     }
     if (is_array($options->highlight_terms)) {
         $text = highlight_terms($text, $options->highlight_terms);
diff --git a/html/user/create_profile.php b/html/user/create_profile.php
index 8c810a04f4..7921d837e1 100644
--- a/html/user/create_profile.php
+++ b/html/user/create_profile.php
@@ -18,7 +18,7 @@
 
 // TODO: the following is organized in a funky way.  Clean it up
 
-require_once("..inc/util.inc");
+require_once("../inc/util.inc");
 require_once("../inc/profile.inc");
 require_once("../inc/akismet.inc");
 require_once("../inc/recaptchalib.php");
@@ -54,11 +54,11 @@ function show_picture_option($profile) {
     row1(tra("Picture"));
 
     $warning = "";
-    if (profile_screening() && $profile->has_picture) {
+    if (profile_screening() && $profile && $profile->has_picture) {
         $warning = offensive_profile_warning($profile->verification);
     }
 
-    if (($profile) && ($profile->has_picture)) {
+    if ($profile && ($profile->has_picture)) {
         echo "
 <tr><td colspan=2>
 <table border=0 cellpadding=5
diff --git a/html/user/forum_report_post.php b/html/user/forum_report_post.php
index c008bc3b0d..cce16bbbe7 100644
--- a/html/user/forum_report_post.php
+++ b/html/user/forum_report_post.php
@@ -32,8 +32,11 @@ check_get_args(array("post", "submit", "reason", "tnow", "ttok"));
 $postId = get_int('post');
 
 $post = BoincPost::lookup_id($postId);
+if (!$post) error_page("No such post.");
 $thread = BoincThread::lookup_id($post->thread);
+if (!$thread) error_page("No such thread.");
 $forum = BoincForum::lookup_id($thread->forum);
+if (!$forum) error_page("No such forum.");
 
 $user = get_logged_in_user();
 BoincForumPrefs::lookup($user);
diff --git a/html/user/forum_thread.php b/html/user/forum_thread.php
index bf4d7eef56..a85ce95c12 100644
--- a/html/user/forum_thread.php
+++ b/html/user/forum_thread.php
@@ -53,11 +53,11 @@ if ($threadid < 1) {
 }
 
 $thread = BoincThread::lookup_id($threadid);
-$forum = BoincForum::lookup_id($thread->forum);
 
 if (!$thread) {
     error_page("Bad thread ID");
 }
+$forum = BoincForum::lookup_id($thread->forum);
 
 if (!is_forum_visible_to_user($forum, $logged_in_user)) {
     if ($logged_in_user) {