diff --git a/interface/web/admin/form/server_config.tform.php b/interface/web/admin/form/server_config.tform.php
index 93094629ac934d1259ce78a951cca93b10d3f266..fbf23503cc4621552e7df632f7485784a058441f 100644
--- a/interface/web/admin/form/server_config.tform.php
+++ b/interface/web/admin/form/server_config.tform.php
@@ -190,7 +190,7 @@ $form["tabs"]['server'] = array(
 			'validators' => array(	0 => array('type' => 'NOTEMPTY',
 										'errmsg' => 'tmpdir_path_error_empty'),
 									1 => array ( 	'type' => 'REGEX',
-										'regex' => '/^\/[a-zA-Z0-9\.\-\_\/]{5,128}$/',
+										'regex' => "/(|^\\/{1,2}(?:[\\w-]+[.]?\\/?){5,128})$/",
 										'errmsg'=> 'tmpdir_path_error_regex'),
 			),
 			'value' => '',