diff --git a/phpBB/includes/usercp_register.php b/phpBB/includes/usercp_register.php
index e912ad363b..67a44e0cf5 100644
--- a/phpBB/includes/usercp_register.php
+++ b/phpBB/includes/usercp_register.php
@@ -409,9 +409,9 @@ if ( isset($HTTP_POST_VARS['submit']) )
 			// Error is already triggered, since one field is empty.
 			$error = TRUE;
 		}
-		else if ( $username != $userdata['username'] || $mode == 'register' )
+		else if ( $username != $userdata['username'] || $mode == 'register')
 		{
-			if (strtolower($username) != strtolower($userdata['username']))
+			if (strtolower($username) != strtolower($userdata['username']) || $mode == 'register')
 			{
 				$result = validate_username($username);
 				if ( $result['error'] )