diff --git a/admin/tool/mobile/classes/api.php b/admin/tool/mobile/classes/api.php
index 9885b4e454f..af205ab932c 100644
--- a/admin/tool/mobile/classes/api.php
+++ b/admin/tool/mobile/classes/api.php
@@ -81,7 +81,7 @@ class api {
                     );
 
                     // All the mobile packages must be under the plugin mobile directory.
-                    $package = $path . DIRECTORY_SEPARATOR . 'mobile' . DIRECTORY_SEPARATOR . $addonname . '.zip';
+                    $package = $path . '/mobile/' . $addonname . '.zip';
                     if (file_exists($package)) {
                         $plugininfo['fileurl'] = $CFG->wwwroot . '' . str_replace($CFG->dirroot, '', $package);
                         $plugininfo['filehash'] = sha1_file($package);