diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0ab053490..10a011314 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,7 +24,6 @@ set(CMAKE_INSTALL_INCLUDEDIR include/lib3mf CACHE PATH "directory for installing
 
 option(USE_INCLUDED_ZLIB "Use included zlib" ON)
 option(USE_INCLUDED_LIBZIP "Use included libzip" ON)
-option(USE_INCLUDED_GTEST "Used included gtest" ON)
 option(USE_INCLUDED_SSL "Use included libressl" ON)
 option(BUILD_FOR_CODECOVERAGE "Build for code coverage analysis" OFF)
 option(STRIP_BINARIES "Strip binaries (on non-apple)" ON)
diff --git a/Include/Common/NMR_ErrorConst.h b/Include/Common/NMR_ErrorConst.h
index 0d461286a..aaaf60fb8 100644
--- a/Include/Common/NMR_ErrorConst.h
+++ b/Include/Common/NMR_ErrorConst.h
@@ -1228,6 +1228,9 @@ Model error codes (0x8XXX)
 // A component resource is invalid
 #define NMR_ERROR_INVALIDCOMPONENTRESOURCE 0x810D
 
+// A keystore element is not base64 encoded
+#define NMR_ERROR_KEYSTOREINVALIDENCODING 0x810E
+
 /*-------------------------------------------------------------------
 XML Parser Error Constants (0x9XXX)
 -------------------------------------------------------------------*/
diff --git a/Source/Common/NMR_Exception.cpp b/Source/Common/NMR_Exception.cpp
index 0edd80259..6f5187159 100644
--- a/Source/Common/NMR_Exception.cpp
+++ b/Source/Common/NMR_Exception.cpp
@@ -418,6 +418,7 @@ namespace NMR {
 		case NMR_ERROR_KEYSTOREDUPLICATEACCESSRIGHT: return "An AccessRight already exists for this consumer in a ResourceDataGroup";
 		case NMR_ERROR_KEYSTOREDUPLICATERESOURCEDATAGROUP: return "A resource data group already exist for this keyuuid";
 		case NMR_ERROR_KEYSTOREINVALIDALGORITHM: return "The algorithm attribute is invalid";
+		case NMR_ERROR_KEYSTOREINVALIDENCODING: return "The keystore element value is not base64 encoded.";
 		case NMR_ERROR_KEYSTOREINVALIDCOMPRESSION: return "The KeyStore ResourceData compression is invalid";
 		case NMR_ERROR_KEYSTOREINVALIDCIPHERVALUE: return "Invalid CipherValue elment value";
 		case NMR_ERROR_KEYSTOREINVALIDMGF: return "The mfgalgorithm attribute has invalid value";
diff --git a/Source/Model/Reader/SecureContent101/NMR_ModelReaderNode_KeyStoreCEKParams.cpp b/Source/Model/Reader/SecureContent101/NMR_ModelReaderNode_KeyStoreCEKParams.cpp
index 378f4aed7..70552a1b8 100644
--- a/Source/Model/Reader/SecureContent101/NMR_ModelReaderNode_KeyStoreCEKParams.cpp
+++ b/Source/Model/Reader/SecureContent101/NMR_ModelReaderNode_KeyStoreCEKParams.cpp
@@ -131,6 +131,7 @@ namespace NMR {
 		}
 		catch (...) {
 			// base64_decode throws an exception if the input is not valid base64
+			m_pWarnings->addException(CNMRException(NMR_ERROR_KEYSTOREINVALIDENCODING), mrwInvalidOptionalValue);
         }
 	}
 }
diff --git a/Source/Model/Reader/SecureContent101/NMR_ModelReaderNode_KeyStoreCipherValue.cpp b/Source/Model/Reader/SecureContent101/NMR_ModelReaderNode_KeyStoreCipherValue.cpp
index e7a61218d..5b9dcc55e 100644
--- a/Source/Model/Reader/SecureContent101/NMR_ModelReaderNode_KeyStoreCipherValue.cpp
+++ b/Source/Model/Reader/SecureContent101/NMR_ModelReaderNode_KeyStoreCipherValue.cpp
@@ -77,6 +77,7 @@ namespace NMR {
 			}
 			catch (...) {
 				// base64_decode throws an exception if the input is not valid base64
+				m_pWarnings->addException(CNMRException(NMR_ERROR_KEYSTOREINVALIDENCODING), NMR::eModelWarningLevel::mrwInvalidMandatoryValue);
             }
 		}
 	}
diff --git a/Tests/CPP_Bindings/Source/SecureContent.cpp b/Tests/CPP_Bindings/Source/SecureContent.cpp
index 9d4fe82f4..021db7328 100644
--- a/Tests/CPP_Bindings/Source/SecureContent.cpp
+++ b/Tests/CPP_Bindings/Source/SecureContent.cpp
@@ -395,7 +395,7 @@ namespace Lib3MF {
 
 	TEST_F(SecureContentT, ModelReaderKeyStoreNoAttributesWarnings) {
 		PReader reader3MF = readKeyStore(NEGATIVEUNENCRYPTEDKEYSTOREMISSINGATTRIBUTES);
-		CheckReaderWarnings(reader3MF, 6);
+		CheckReaderWarnings(reader3MF, 8);
 		Lib3MF_uint32 iWarning = 0;
 
 		// NMR_ERROR_KEYSTOREMISSINGCONSUMERID
@@ -418,21 +418,32 @@ namespace Lib3MF {
 		reader3MF->GetWarning(3, iWarning);
 		ASSERT_EQ(0x8105, iWarning);
 
+		// NMR_ERROR_KEYSTOREINVALIDENCODING 
+		// invalid key store element value in ResourceData
+		reader3MF->GetWarning(4, iWarning);
+		ASSERT_EQ(0x810E, iWarning);
+
+		// NMR_ERROR_KEYSTOREINVALIDENCODING 
+		// invalid key store element value in ResourceData
+		reader3MF->GetWarning(5, iWarning);
+		ASSERT_EQ(0x810E, iWarning);
+
+
 		// NMR_ERROR_KEYSTOREMISSINGALGORTHM
 		// missing encryptionalgorithm on cekparams
-		reader3MF->GetWarning(4, iWarning);
+		reader3MF->GetWarning(6, iWarning);
 		ASSERT_EQ(0x810A, iWarning);
 
 		// NMR_ERROR_MISSINGUUID
 		//missing guid on keystore
-		reader3MF->GetWarning(5, iWarning);
+		reader3MF->GetWarning(7, iWarning);
 		ASSERT_EQ(0x80B0, iWarning);
 
 	}
 
 	TEST_F(SecureContentT, ModelReaderKeyStoreInvalidAttributesWarnings) {
 		PReader reader3MF = readKeyStore(NEGATIVEUNENCRYPTEDKEYSTOREINVALIDATTRIBUTES);
-		CheckReaderWarnings(reader3MF, 8);
+		CheckReaderWarnings(reader3MF, 10);
 		Lib3MF_uint32 iWarning = 0;
 
 		// NMR_ERROR_KEYSTOREDUPLICATECONSUMERID
@@ -474,6 +485,16 @@ namespace Lib3MF {
 		// invalid compression attribute in ResourceData
 		reader3MF->GetWarning(7, iWarning);
 		ASSERT_EQ(0x80F8, iWarning);
+
+		// NMR_ERROR_KEYSTOREINVALIDENCODING 
+		// invalid key store element value in ResourceData
+		reader3MF->GetWarning(8, iWarning);
+		ASSERT_EQ(0x810E, iWarning);
+
+		// NMR_ERROR_KEYSTOREINVALIDENCODING 
+		// invalid key store element value in ResourceData
+		reader3MF->GetWarning(9, iWarning);
+		ASSERT_EQ(0x810E, iWarning);
 	}
 	
 	TEST_F(SecureContentT, CheckKeyStoreConsumers) {