diff --git a/rstan/rstan/inst/misc/stan_progress.html b/rstan/rstan/inst/misc/stan_progress.html
index 758471f2f..bb74b95d4 100644
--- a/rstan/rstan/inst/misc/stan_progress.html
+++ b/rstan/rstan/inst/misc/stan_progress.html
@@ -3,6 +3,6 @@
 <meta charset="utf-8">
 <title>%title%</title>
 </head>
-<iframe src="%filename%" style="width: 100%; height: 100%; border: 0">
+<iframe src="file://%filename%" style="width: 100%; height: 100%; border: 0">
 </iframe>
 </html>