diff --git a/pluginfile.php b/pluginfile.php
index 7a5bf6e80c5..1585040e6e2 100644
--- a/pluginfile.php
+++ b/pluginfile.php
@@ -36,7 +36,7 @@ $forcedownload = optional_param('forcedownload', 0, PARAM_BOOL);
 // relative path must start with '/'
 if (!$relativepath) {
     print_error('invalidargorconf');
-} else if ($relativepath{0} != '/') {
+} else if ($relativepath[0] != '/') {
     print_error('pathdoesnotstartslash');
 }