diff --git a/PDFMerger.php b/PDFMerger.php
index 26928f3..c5443d8 100644
--- a/PDFMerger.php
+++ b/PDFMerger.php
@@ -115,7 +115,7 @@ public function merge($outputmode = 'browser', $outputpath = 'newfile.pdf')
 		}
 		else
 		{
-			if($fpdi->Output($outputpath, $mode))
+			if($fpdi->Output($outputpath, $mode) == '')
 			{
 				return true;
 			}
@@ -190,4 +190,4 @@ private function _rewritepages($pages)
 		return $newpages;
 	}
 	
-}
\ No newline at end of file
+}