diff --git a/register_backend.php b/register_backend.php
index a1eb5fced4898de77a93582c6ff7067bd22f2eca..f3b5c57310ab1346eac13fbaa4cf5664b2097494 100644
--- a/register_backend.php
+++ b/register_backend.php
@@ -13,15 +13,31 @@ if(isset($_POST['login']) && isset($_POST['password']) && !empty($_POST['login']
 	{
 		if($_POST['password'] === $_POST['passwd_confc'])
 		{
-			if($_POST['type'] === monitored) 
+			if($_POST['type'] === 'monitored') 
 			{
-				$user = \BackEnd\User\MonitoredUser::addUser($_POST['login'],$_POST['email'],$_POST['password'],
+				try
+				{
+					$user = \BackEnd\User\MonitoredUser::addUser($_POST['login'],$_POST['email'],$_POST['password'],
 					$_POST['name'],$_POST['address'], $_POST['tel']);
+				}
+				catch(Exception $e)
+				{
+					header('Location: index.php?err=4');
+					exit;
+				}
 			}
-			else if ($_POST['type'] === supervisor)
+			else if ($_POST['type'] === 'supervisor')
 			{
-				$user = \BackEnd\User\SupervisorUser::addUser($_POST['login'],$_POST['email'],$_POST['password'],
+				try
+				{
+					$user = \BackEnd\User\SupervisorUser::addUser($_POST['login'],$_POST['email'],$_POST['password'],
 					$_POST['name'],$_POST['address'], $_POST['tel']);
+					}
+				catch(Exception $e)
+				{
+					header('Location: index.php?err=5');
+					exit;
+				}
 			}
 			else 
 			{