private bool CheckSslCertificate(object sender, System.Security.Cryptography.X509Certificates.X509Certificate certificate, System.Security.Cryptography.X509Certificates.X509Chain chain, System.Net.Security.SslPolicyErrors sslPolicyErrors) { var startTime = DateTime.Parse(certificate.GetEffectiveDateString()); var endTime = DateTime.Parse(certificate.GetExpirationDateString()); if (startTime <= DateTime.Now && endTime >= DateTime.Now && certificate.GetIssuerName().Contains("Philips Hue")) { return(true); } else { return(false); } }