diff --git a/code/CMSMain.php b/code/CMSMain.php
index <HASH>..<HASH> 100644
--- a/code/CMSMain.php
+++ b/code/CMSMain.php
@@ -722,8 +722,8 @@ HTML;
 	 */
 	function sidereport() {
 		$reportClass = $this->urlParams['ID'];
-		$report = new $reportClass();
-		return $report->getHTML();
+		$report = ClassInfo::exists($reportClass) ? new $reportClass() : false;
+		return $report ? $report->getHTML() : false;
 	}
 	/**
 	 * Get the versions of the current page
BUGFIX Side reports weren't working on initial opening of the side tab

git-svn-id: svn://svn.silverstripe.com/silverstripe/open/modules/cms/trunk@<I> <I>b<I>ca-7a2a-<I>-9d3b-<I>d<I>a<I>a9