diff --git a/src/www/services_captiveportal_filemanager.php b/src/www/services_captiveportal_filemanager.php
index 67b8471b2..c35b10d7d 100644
--- a/src/www/services_captiveportal_filemanager.php
+++ b/src/www/services_captiveportal_filemanager.php
@@ -30,6 +30,7 @@
 require_once("guiconfig.inc");
 require_once("captiveportal.inc");
 require_once("services.inc");
+require_once("interfaces.inc");
 
 
 $captiveportal_element_sizelimit = 1048576;
diff --git a/src/www/services_captiveportal_ip.php b/src/www/services_captiveportal_ip.php
index 672511ca5..ca0edde92 100644
--- a/src/www/services_captiveportal_ip.php
+++ b/src/www/services_captiveportal_ip.php
@@ -29,6 +29,7 @@
 require_once("guiconfig.inc");
 require_once("captiveportal.inc");
 require_once("services.inc");
+require_once("interfaces.inc");
 
 $cpzone = $_GET['zone'];
 if (isset($_POST['zone'])) {
diff --git a/src/www/services_captiveportal_mac.php b/src/www/services_captiveportal_mac.php
index dabb0e32c..84b017e88 100644
--- a/src/www/services_captiveportal_mac.php
+++ b/src/www/services_captiveportal_mac.php
@@ -30,6 +30,7 @@
 require_once("guiconfig.inc");
 require_once("captiveportal.inc");
 require_once("services.inc");
+require_once("interfaces.inc");
 
 global $cpzone;
 global $cpzoneid;