title: Getting null when trying to get AsymmetricCipherKeyPair
body: <p>I have this piece of code whose equivalents I have found in multiple places. But it is returning null when I am using it. </p>
  
  <pre><code>  using Org.BouncyCastle.OpenSsl;
    using Org.BouncyCastle.Crypto;
    using Org.BouncyCastle.Security;  
  
   string aToBeEncrypted= "asdfghikoksadjfkjsdfjsljfsadjf";
   string pemFilename = @"M:\ConnectivityPackage_meltemi_KeyStore.pem";
  
   byte[] plaintext = System.Text.Encoding.UTF8.GetBytes(aToBeEncrypted);
  
   AsymmetricCipherKeyPair keyPair;
  
   using (var reader = File.OpenText(pemFilename))
      keyPair = (AsymmetricCipherKeyPair)new PemReader(reader).ReadObject();
  </code></pre>
  
  <p>keyPair is a null object. What is it that I am doing wrong or is it something with the pem file?</p>