diff --git a/mod/forum/lib.php b/mod/forum/lib.php
index bd9423e42a7..b2763d9b415 100644
--- a/mod/forum/lib.php
+++ b/mod/forum/lib.php
@@ -2615,7 +2615,12 @@ function forum_file_area_name($post) {
 }
 
 function forum_file_area($post) {
-    return make_upload_directory( forum_file_area_name($post) );
+    $path = forum_file_area_name($post);
+    if ($path) {
+        return make_upload_directory($path);
+    } else {
+        return false;
+    }
 }
 
 function forum_delete_old_attachments($post, $exception="") {