diff --git a/tests/unit-tests/security/tpm/back-end.t.cpp b/tests/unit-tests/security/tpm/back-end.t.cpp
index ad8e39c..f118099 100644
--- a/tests/unit-tests/security/tpm/back-end.t.cpp
+++ b/tests/unit-tests/security/tpm/back-end.t.cpp
@@ -221,6 +221,8 @@
 
   tpm.importKey(keyName, privateKeyBuffer->data(), privateKeyBuffer->size(), password.c_str(), password.size());
   BOOST_CHECK_EQUAL(tpm.hasKey(keyName), true);
+  BOOST_CHECK_THROW(tpm.importKey(keyName, privateKeyBuffer->data(), privateKeyBuffer->size(), password.c_str(), password.size()),
+                    BackEnd::Error);
 
   ConstBufferPtr exportedKey = tpm.exportKey(keyName, password.c_str(), password.size());
   BOOST_CHECK_EQUAL(tpm.hasKey(keyName), true);
@@ -236,6 +238,7 @@
 
   tpm.deleteKey(keyName);
   BOOST_CHECK_EQUAL(tpm.hasKey(keyName), false);
+  BOOST_CHECK_THROW(tpm.exportKey(keyName, password.c_str(), password.size()), BackEnd::Error);
 }
 
 BOOST_AUTO_TEST_CASE(RandomKeyId)
diff --git a/tests/unit-tests/security/v2/key-chain.t.cpp b/tests/unit-tests/security/v2/key-chain.t.cpp
index a874464..9575754 100644
--- a/tests/unit-tests/security/v2/key-chain.t.cpp
+++ b/tests/unit-tests/security/v2/key-chain.t.cpp
@@ -1,5 +1,5 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
+/*
  * Copyright (c) 2013-2017 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
@@ -365,6 +365,7 @@
   Block block = exported->wireEncode();
 
   m_keyChain.deleteIdentity(id);
+  BOOST_CHECK_THROW(m_keyChain.exportSafeBag(cert, "1234", 4), KeyChain::Error);
 
   BOOST_CHECK_EQUAL(m_keyChain.getTpm().hasKey(cert.getKeyName()), false);
   BOOST_CHECK_EQUAL(m_keyChain.getPib().getIdentities().size(), 0);
@@ -372,6 +373,7 @@
   SafeBag imported;
   imported.wireDecode(block);
   m_keyChain.importSafeBag(imported, "1234", 4);
+  BOOST_CHECK_THROW(m_keyChain.importSafeBag(imported, "1234", 4), KeyChain::Error);
 
   BOOST_CHECK_EQUAL(m_keyChain.getTpm().hasKey(cert.getKeyName()), true);
   BOOST_CHECK_EQUAL(m_keyChain.getPib().getIdentities().size(), 1);