diff --git a/public/index.php b/public/index.php
index 99c7c092..88276ef6 100644
--- a/public/index.php
+++ b/public/index.php
@@ -194,6 +194,9 @@ if (isset($user) && $p != "user_messages")
 if (isset($user) && $user['Gekommen'] == 0)
   $content = error(_("You are not marked as arrived. Please go to heaven's desk, get your angel badge and/or tell them that you arrived already."), true) . $content;
   
+if($enable_tshirt_size && $user['Size'] == "")
+  $content = error(_("You need to specify a tshirt size in your settings!"), true) . $content;
+
   // Erzengel Hinweis für unbeantwortete Fragen
 if (isset($user) && $p != "admin_questions")
   $content = admin_new_questions() . $content;