❔ X509 Certificate from base64 string

CryptographicException: Unable to decode certificate.

MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBALOexE7WXZM/aq8S0umcDGptu7BHSF5KNq/O5PA1jP54HzNQuSDjyd/3Fp3SOWUr6RC8nQKfYqPRXkOVce73h50CAwEAAQ==

final X509EncodedKeySpec keySpec = new X509EncodedKeySpec(Base64.getDecoder().decode(publicKeyString.getBytes()));

byte[] publicKeyBytes = Convert.FromBase64String(base64publicKey);
X509Certificate2 cert = new X509Certificate2(publicKeyBytes);
return cert;

byte[] publicKeyBytes = Convert.FromBase64String(base64publicKey);
X509Certificate2 cert = null;
string certFile = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
try {
    File.WriteAllBytes(certFile, publicKeyBytes);
    string certText = File.ReadAllText(certFile);
    cert = new X509Certificate2(certFile);
} finally {
    File.Delete(certFile);
}
return cert;