diff --git a/install/install.php b/install/install.php
index 50e19e943e66f3e00a36bdc86396c7c527a71b4f..d2aaf6087c4f06cb4a6761710c74128417a574ef 100644
--- a/install/install.php
+++ b/install/install.php
@@ -97,6 +97,8 @@ require_once 'lib/classes/tpl.inc.php';
     die('We will stop here. There is already a ISPConfig installation, use the update script to update this installation.');
 }*/
 
+if(!is_installed('patch')) die('The patch command is missing. Install patch command and start installation again.');
+
 //** Get distribution identifier
 $dist = get_distname();
 
diff --git a/install/update.php b/install/update.php
index 53a2f73425942f1dee4cfb6eb94795ccea547099..360d88bff3fbaec4c7579e6e163c350b33ac2fe0 100644
--- a/install/update.php
+++ b/install/update.php
@@ -98,6 +98,8 @@ if(is_dir('/root/ispconfig') || is_dir('/home/admispconfig')) {
 	die('This software cannot be installed on a server wich runs ISPConfig 2.x.');
 }
 
+if(!is_installed('patch')) die('The patch command is missing. Install patch command and start installation again.');
+
 //** Get distribution identifier
 $dist = get_distname();