MailAddress.Certificate2 Property

Gets or sets the associating digital certificate for digital signature and encryption (S/MIME).

[Visual Basic]
Public Property Certificate2 As X509Certificate2

[C#]
public X509Certificate2 Certificate2 {get; set;}

[C++]
public: __property X509Certificate2^ get_Certificate2();
public: __property void set_Certificate2(X509Certificate2^);

[JScript]
public function get Certificate2() : X509Certificate2;
public function set Certificate2(X509Certificate2);

Property Value

Remarks

RSASSA-PSS Signature and RSA-OAEP Encryption

If you need to use RSASSA-PSS signature scheme, you need a special version of EASendMail, please have a look at this topic:
RSASSA-PSS + RSA-OAEP Encryption with SHA256

Example

[Visual Basic, C#] The following example demonstrates how to load certificate to sign email content with EASendMail SMTP Component. To get the full samples of EASendMail, please refer to Samples section.

[VB - Sign Email with Certificate]
Imports EASendMail
Imports System.Security.Cryptography.X509Certificates

Private Function _findCertificate(storeName As String, emailAddress As String) As X509Certificate2  

    Dim cert As X509Certificate2 = Nothing
    Dim store As New X509Store(storeName, StoreLocation.CurrentUser)

    store.Open(OpenFlags.ReadOnly)
    Dim certfiicates As X509Certificate2Collection = store.Certificates.Find(X509FindType.FindBySubjectName, emailAddress, True)
    If certfiicates.Count > 0 Then
        cert = certfiicates(0)
    End If

    store.Close()

    _findCertificate = cert
End Function

Try
    Dim oMail As SmtpMail = New SmtpMail("TryIt")
    oMail.From = New MailAddress("test@emailarchitect.net")

    Dim signerCertificate As X509Certificate2 = _findCertificate("My", oMail.From.Address)
    If signerCertificate Is Nothing Then
        Throw New Exception("No signer certificate found for " + oMail.From.Address + "!")
    End If

    oMail.From.Certificate2 = signerCertificate
    ' You can also load the signer certificate from a pfx file.
    '
    ' Dim pfxPath As String = "D:\TestCerts\signer.pfx"
    ' Dim signerCertFromPfx As X509Certificate2 = New X509Certificate2(pfxPath,
    '        "nosecret",
    ' X509KeyStorageFlags.Exportable Or X509KeyStorageFlags.UserKeySet)
    ' oMail.From.Certificate2 = signerCertFromPfx

    ' If you use it in web application,
    ' please use  X509KeyStorageFlags.Exportable Or X509KeyStorageFlags.MachineKeySet

    ' If you use it in .NET core application
    ' please use X509KeyStorageFlags.Exportable Or X509KeyStorageFlags.EphemeralKeySet

Catch exp As Exception
    Console.WriteLine("No sign certificate found for sender email: {0}", exp.Message)
End Try


[C# - Sign Email with Certificate]
using System.Security.Cryptography.X509Certificates;
using EASendMail;

X509Certificate2 _findCertificate(string storeName, string emailAddress)
{
    X509Certificate2 cert = null;

    X509Store store = new X509Store(storeName, StoreLocation.CurrentUser);
    store.Open(OpenFlags.ReadOnly);

    X509Certificate2Collection certfiicates = store.Certificates.Find(X509FindType.FindBySubjectName, emailAddress, true);
    if (certfiicates.Count > 0)
    {
        cert = certfiicates[0];
    }

    store.Close();

    return cert;
}

try
{
    SmtpMail oMail = new SmtpMail("TryIt");
    oMail.From = "test@adminsystem.com";

    X509Certificate2 signerCertificate = _findCertificate("My", oMail.From.Address);
    if (signerCertificate == null)
        throw new Exception("No signer certificate found for " + oMail.From.Address + "!");

    oMail.From.Certificate2 = signerCertificate;

    // You can also load the signer certificate from a pfx file.
    /* string pfxPath = "D:\\TestCerts\\signer.pfx";
    X509Certificate2 signerCertFromPfx = new X509Certificate2(pfxPath,
        "nosecret",
        X509KeyStorageFlags.Exportable | X509KeyStorageFlags.UserKeySet);

    oMail.From.Certificate2 = signerCertFromPfx;
    */
    // If you use it in web application,
    // please use  X509KeyStorageFlags.Exportable | X509KeyStorageFlags.MachineKeySet

    // If you use it in .NET core application
    // please use X509KeyStorageFlags.Exportable | X509KeyStorageFlags.EphemeralKeySet
}
catch (Exception exp)
{
    Console.WriteLine("No sign certificate found {0}", exp.Message);
}


[VB - Encrypt Email]

Imports EASendMail
Imports System.Security.Cryptography.X509Certificates

Private Function _findCertificate(storeName As String, emailAddress As String) As X509Certificate2  

    Dim cert As X509Certificate2 = Nothing
    Dim store As New X509Store(storeName, StoreLocation.CurrentUser)

    store.Open(OpenFlags.ReadOnly)
    Dim certfiicates As X509Certificate2Collection = store.Certificates.Find(X509FindType.FindBySubjectName, emailAddress, True)
    If certfiicates.Count > 0 Then
        cert = certfiicates(0)
    End If

    store.Close()

    _findCertificate = cert
End Function

Dim oMail As SmtpMail = New SmtpMail("TryIt")
oMail.From = New MailAddress("test@adminsystem.com")
oMail.To = New AddressCollection("encrypt1@adminsystem.com, encrypt2@adminsystem.com")

For i As Integer = 0 To oMail.[To].Count - 1
    Dim oAddress As MailAddress = oMail.[To](i)

    Dim encryptCert As X509Certificate2 = _findCertificate("AddressBook", oAddress.Address)
    If encryptCert Is Nothing Then
        encryptCert = _findCertificate("My", oAddress.Address)
    End If

    If encryptCert Is Nothing Then
        Throw New Exception("No encryption certificate found for " + oAddress.Address + "!")
    End If

    oAddress.Certificate2 = encryptCert

    ' You can also load the encryptor certificate from a cer file Like this

    ' Dim cerPath As String = "D:\TestCerts\encryptor.cer"
    ' Dim encryptCertFromFile = New X509Certificate2(cerPath)
    ' oAddress.Certificate2 = encryptCertFromFile
Next

[C# - Encrypt Email]
using System.Security.Cryptography.X509Certificates;
using EASendMail;

X509Certificate2 _findCertificate(string storeName, string emailAddress)
{
    X509Certificate2 cert = null;

    X509Store store = new X509Store(storeName, StoreLocation.CurrentUser);
    store.Open(OpenFlags.ReadOnly);

    X509Certificate2Collection certfiicates = store.Certificates.Find(X509FindType.FindBySubjectName, emailAddress, true);
    if (certfiicates.Count > 0)
    {
        cert = certfiicates[0];
    }

    store.Close();

    return cert;
}

SmtpMail oMail = new SmtpMail("TryIt");
oMail.From = "test@adminsystem.com";
oMail.To = "encrypt1@adminsystem.com, encrypt2@adminsystem.com";

for (int i = 0; i < oMail.To.Count; i++)
{
    MailAddress oAddress = oMail.To[i];

    X509Certificate2 encryptCert = _findCertificate("AddressBook", oAddress.Address);
    if (encryptCert == null)
        encryptCert = _findCertificate("My", oAddress.Address);

    if (encryptCert == null)
        throw new Exception("No encryption certificate found for " + oAddress.Address + "!");

    oAddress.Certificate2 = encryptCert;

    // You can also load the encryptor certificate from a cer file like this
    /* 
    string cerPath = "D:\\TestCerts\\encryptor.cer";
    X509Certificate2 encryptCertFromFile = new X509Certificate2(cerPath);
    oAddress.Certificate2 = encryptCertFromFile;
    */
}

See Also

From, ReplyTo, Sender and Return-Path
SmtpMail.From Property
SmtpMail.ReplyTo Property
SmtpMail.Sender Property
SmtpMail.ReturnPath Property
SmtpMail.To Property
SmtpMail.Cc Property
SmtpMail.Bcc Property

Online Examples

Sign Email - VB
Encrypt Email - VB
Sign Email - C#
Encrypt Email - C#
Sign Email - C++/CLI
Encrypt Email - C++/CLI