diff --git a/composer.json b/composer.json
index 3a7e38f42e..19bd982d74 100644
--- a/composer.json
+++ b/composer.json
@@ -61,5 +61,10 @@
         "App\\Providers\\ThemeServiceProvider"
       ]
     }
+  },
+  "scripts": {
+    "post-autoload-dump": [
+      "Roots\\Acorn\\ComposerScripts::postAutoloadDump"
+    ]
   }
 }
diff --git a/functions.php b/functions.php
index 9b1b0c0947..104579c287 100644
--- a/functions.php
+++ b/functions.php
@@ -31,7 +31,7 @@
 
 if (! function_exists('\Roots\bootloader')) {
     wp_die(
-        __('You need to install Acorn to use this theme.', 'sage'),
+        __('You need to install Acorn to use this theme. Run <code>composer install</code> in your theme directory to fix this.', 'sage'),
         '',
         [
             'link_url' => 'https://roots.io/acorn/docs/installation/',