diff --git a/lib/installer.php b/lib/installer.php
index 7936d5d5d1..78461efb72 100644
--- a/lib/installer.php
+++ b/lib/installer.php
@@ -446,7 +446,7 @@ abstract class Installer
             case 'mysqli':
                 $res = $conn->query($stmt);
                 if ($res === false) {
-                    $error = $conn->error();
+                    $error = $conn->error;
                 }
                 break;
             case 'pgsql':