function TForm1.VerifyDetachedSignature(sFileToVerifyPath, sSignaturePath
  : String): Boolean;
var
  veriPara: CRYPT_VERIFY_MESSAGE_PARA;
  mStreamIn, mStreamSignIn: TMemoryStream;
  arrDataPointer: array of Pointer;
  arrDataSize: array of DWORD;
  MessageArray: pacarpbyte;
  SizeArray: pacarDWORD;
  pCert: PCCERT_CONTEXT;
  nameString, issuerString: string;
  stSigner, stDescription: string;
  f1: File;
begin
  cxMemo1.Clear;
  cxMemo1.Lines.Add('Проверка отсоединенной цифровой подписи');
  Result := false;
  try
    mStreamIn := TMemoryStream.Create;
    mStreamIn.LoadFromFile(sFileToVerifyPath);
    SetLength(arrDataPointer, 1);
    SetLength(arrDataSize, 1);
    arrDataPointer[0] := mStreamIn.memory;
    arrDataSize[0] := mStreamIn.Size;
    mStreamSignIn := TMemoryStream.Create;
    mStreamSignIn.LoadFromFile(sSignaturePath);
    FillChar(veriPara, SizeOf(CRYPT_VERIFY_MESSAGE_PARA), #0);
    veriPara.cbSize := SizeOf(CRYPT_VERIFY_MESSAGE_PARA);
    veriPara.dwMsgAndCertEncodingType := PKCS_7_ASN_ENCODING or
      X509_ASN_ENCODING;
    if CryptVerifyDetachedMessageSignature(@veriPara, 0, mStreamSignIn.memory,
      mStreamSignIn.Size, 1, Pointer(arrDataPointer), Pointer(arrDataSize), nil)
    then
    begin
      cxMemo1.Lines.Add('Подпись верна');
      if Assigned(pCert.HCERTSTORE) then
      begin
        [color=red]if CertVerifyTimeValidity(nil, pCert^.pCertInfo) = 0 then[/color]
        begin
          nameString := DecodeName(@pCert.pCertInfo.Subject);
          issuerString := DecodeName(@pCert.pCertInfo.Issuer);
          stDescription := Format('%s %s', [nameString, issuerString]);
          cxMemo1.Lines.Add(Format('%s', [stDescription]));
        end
        else
          cxMemo1.Lines.Add('Сертификат просрочен');
      end
      else
        cxMemo1.Lines.Add('Сертификат не найден');
      Result := true;
    end
    else
    begin
      cxMemo1.Lines.Add('Подписи нет');
    end;
    if not(CertFreeCertificateContext(pCert)) then
      cxMemo1.Lines.Add('Не удалось удалить контекст сертификата');
  finally
    FreeAndNil(mStreamIn);
    FreeAndNil(mStreamSignIn);
  end;
end;

if CryptVerifyDetachedMessageSignature(@veriPara, 0, mStreamSignIn.memory,
      mStreamSignIn.Size, 1, Pointer(arrDataPointer), Pointer(arrDataSize), nil)