diff --git a/dev/install/config-form.html b/dev/install/config-form.html
index 47d361524..e04fcdeb9 100644
--- a/dev/install/config-form.html
+++ b/dev/install/config-form.html
@@ -27,6 +27,7 @@
 					document.getElementById('db_password').disabled = '';
 					document.getElementById('admin_username').disabled = '';
 					document.getElementById('admin_password').disabled = '';
+					document.getElementById('devsites').disabled = '';
 					var dbs = getElementsByClassName('databaseClass');
 					for(var i = 0; i < dbs.length; i++) {
 						dbs[i].disabled = '';
@@ -38,6 +39,7 @@
 					document.getElementById('db_password').disabled = 'disabled';
 					document.getElementById('admin_username').disabled = 'disabled';
 					document.getElementById('admin_password').disabled = 'disabled';
+					document.getElementById('devsites').disabled = 'disabled';
 					var dbs = getElementsByClassName('databaseClass');
 					for(var i = 0; i < dbs.length; i++) {
 						dbs[i].disabled = 'disabled';