# SSO login causes "warn Response wasn't properly signed ..." or HTTP400

Attempts to log in through Single Sign-On (SSO) in Chrome result in the following error:

> Error: {“warn”: “Response wasn’t properly signed (resp:false, unenc:true, end:false) for …“}

In Internet Explorer 11, you see an **HTTP400** error instead.

## Cause

Discrepancies exist between the certificates used by the Identity Provider (IdP) and the Service Provider (SP) in the SAML response.

## Solution

1. Retrieve the new federation metadata from the ADFS server.
2. Enter this data in the Zivver SSO settings.

_Overwrite the existing metadata._

Refer to [these steps in the ADFS manual](https://docs.zivver.com/en/admin/sso/microsoft-adfs-internal-network-only.html#set-up-sso-in-zivver-using-the-alternate-method) for further instructions.

Updated on 2026-01-21