if (rmi.CryptoProvider.CanDecrypt == true)
    ShowStatus("   Decryption granted.");
else
    ShowStatus("   CANNOT DECRYPT!");

ShowStatus("   Getting the Package from\n" +
           "      the EncryptedPackage.");
_xpsPackage = ePackage.GetPackage();
if (_xpsPackage == null)
{
    MessageBox.Show("Unable to get Package.");
    return false;
}

// Set a PackageStore Uri reference for the encrypted stream.
// ("sdk://packLocation" is a pseudo URI used by
//  PackUriHelper.Create to define the parserContext.BaseURI
//  that XamlReader uses to access the encrypted data stream.)
Uri packageUri = new Uri(@"sdk://packLocation", UriKind.Absolute);
// Add the URI package
PackageStore.AddPackage(packageUri, _xpsPackage);
// Determine the starting part for the package.
PackagePart startingPart = GetPackageStartingPart(_xpsPackage);

// Set the DocViewer.Document property.
ShowStatus("   Opening in DocumentViewer.");
ParserContext parserContext = new ParserContext();
parserContext.BaseUri = PackUriHelper.Create(
                            packageUri, startingPart.Uri);
parserContext.XamlTypeMapper = XamlTypeMapper.DefaultMapper;
DocViewer.Document = XamlReader.Load(
    startingPart.GetStream(), parserContext)
        as IDocumentPaginatorSource;

// Enable document menu controls.
menuFileClose.IsEnabled = true;
menuFilePrint.IsEnabled = true;
menuViewIncreaseZoom.IsEnabled = true;
menuViewDecreaseZoom.IsEnabled = true;

// Give the DocumentViewer focus.
DocViewer.Focus();