PKCS7 Decrypt MIME

Loads a PKCS7 encrypted MIME file and decrypts.

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Chilkat.Mime mime = new Chilkat.Mime();

bool success;
success = mime.UnlockComponent("Anything for 30-day trial.");
if (success == false) {
    textBox1.Text += mime.LastErrorText + "\r\n";
    return;
}

//  Load the MIME
success = mime.LoadMimeFile("encrypted.mim");
if (success == false) {
    textBox1.Text += mime.LastErrorText + "\r\n";
    return;
}

//  Decrypt...
success = mime.Decrypt();
if (success == false) {
    textBox1.Text += mime.LastErrorText + "\r\n";
    return;
}

//  Display the decrypted MIME:
textBox1.Text += mime.GetMime() + "\r\n";

//  How is it possible to magically decrypt with no information?
//  Answer: It is possible to decrypt if the certificate with private key
//  needed for decryption was previously installed onto the
//  Windows computer.  PKCS7 encrypted (enveloped) data always
//  includes information about the certificate required for
//  decryption.  Chilkat uses it to automatically search the
//  Windows registry-based certificate stores to find the
//  certificate.

//  If the certificate required for decryption was not installed, but
//  you have a PFX file containing the cert + private key,
//  then it may be used like this:

//  The AddPfxSourceFile and/or AddPfxSourceData
//  methods may be called one or more times (one per PFX)
//  to add sources from which the MIME component will
// search for certificates and private keys when decrypting.
string pfxPassword;
pfxPassword = "myPassword";
success = mime.AddPfxSourceFile("myCertAndPrivateKey.pfx",pfxPassword);
if (success == false) {
    textBox1.Text += mime.LastErrorText + "\r\n";
    return;
}

//  Now call Decrypt, and it will search the PFX sources
//  previously added...