After the update to 8.7 we got the message: Sending test message failed. Sending test message failed. An error occurred while attempting to establish an SSL or TLS connection. The server's SSL certificate could not be validated for the following reasons: The server certificate has the following errors: The revocation function was unable to check revocation for the certificate. The revocation function was unable to check revocation because the revocation server was offline. An intermediate certificate has the following errors: The revocation function was unable to check revocation for the certificate. The revocation function was unable to check revocation because the revocation server was offline. An intermediate certificate has the following errors: The revocation function was unable to check revocation for the certificate. The revocation function was unable to check revocation because the revocation server was offline. The remote certificate is invalid according to the validation procedure