diff --git a/mail/inc/class.mail_ui.inc.php b/mail/inc/class.mail_ui.inc.php
index 3b4c293dbe..1356d29f8c 100644
--- a/mail/inc/class.mail_ui.inc.php
+++ b/mail/inc/class.mail_ui.inc.php
@@ -1058,7 +1058,7 @@ class mail_ui
 		);
 		$account = Mail\Account::read($this->mail_bo->profileID);
 		// spamTitan actions
-		if ($account->acc_spam_api)
+		if ($account->acc_spam_api && class_exists('stylite_mail_spamtitan'))
 		{
 			$actions['spamfilter']['children'] = array_merge($actions['spamfilter']['children'], stylite_mail_spamtitan::getActions());
 		}