diff --git a/adm_program/system/common.php b/adm_program/system/common.php
index 4af466f671..d68351290e 100644
--- a/adm_program/system/common.php
+++ b/adm_program/system/common.php
@@ -209,7 +209,7 @@
 // create necessary objects and parameters
 
 // set default theme if no theme was set
-if ($gSettingsManager->has('theme'))
+if (!$gSettingsManager->has('theme'))
 {
     $gSettingsManager->set('theme', 'modern');
 }