diff --git a/install/lib/installer_base.lib.php b/install/lib/installer_base.lib.php
index d39db4492757dcc5fa919742653321bd8b142058..c7ec0ca6f5d30320a499118ffb1d7d29c6c3317f 100644
--- a/install/lib/installer_base.lib.php
+++ b/install/lib/installer_base.lib.php
@@ -554,6 +554,7 @@ class installer_base {
 			$virtual_domains = "' '";
 			
 		$content = str_replace('{hostname}', $conf['hostname'], $content);
+		if(!isset($old_options['DEFAULT_SERVER_LANGUAGE'])) $old_options['DEFAULT_SERVER_LANGUAGE'] = ''
 		$content = str_replace('{default_language}', $old_options['DEFAULT_SERVER_LANGUAGE'], $content);
 		$content = str_replace('{virtual_domains}', $virtual_domains, $content);
 
diff --git a/install/lib/update.lib.php b/install/lib/update.lib.php
index 4cc7355688c572508ea35d9ea96a7197f9e715e8..cf4809fa7b126a67176cd10273e85fc4ec318613 100644
--- a/install/lib/update.lib.php
+++ b/install/lib/update.lib.php
@@ -95,8 +95,8 @@ function updateDbAndIni() {
 	$conf['services']['file'] = ($tmp['file_server'] == 1)?true:false;
 	$conf['services']['db'] = ($tmp['db_server'] == 1)?true:false;
 	$conf['services']['vserver'] = ($tmp['vserver_server'] == 1)?true:false;
-	$conf['services']['proxy'] = ($tmp['proxy_server'] == 1)?true:false;
-	$conf['services']['firewall'] = ($tmp['firewall_server'] == 1)?true:false;
+	$conf['services']['proxy'] = (isset($tmp['proxy_server']) && $tmp['proxy_server'] == 1)?true:false;
+	$conf['services']['firewall'] = (isset($tmp['firewall_server']) && $tmp['firewall_server'] == 1)?true:false;
 	
 	$conf['postfix']['vmail_mailbox_base'] = $ini_array['mail']['homedir_path'];