diff --git a/app/optionChecker/CMakeLists.txt b/app/optionChecker/CMakeLists.txt
index ca1d20a0..e3182458 100644
--- a/app/optionChecker/CMakeLists.txt
+++ b/app/optionChecker/CMakeLists.txt
@@ -9,7 +9,7 @@ include_directories(${AVTRANSCODER_SRC_PATH} ${FFMPEG_INCLUDE_DIR})
 # Add C++11 flag
 if(NOT WIN32)
 	set(CMAKE_CXX_FLAGS "-std=c++0x")
-elseif(NOT MSVC12)
+elseif(${MSVC_VERSION} LESS 1800)
 	message("C++11 not supported, will not build avOptionChecker app.")
 	return()
 endif()
diff --git a/app/presetChecker/CMakeLists.txt b/app/presetChecker/CMakeLists.txt
index d179f514..deb50df5 100644
--- a/app/presetChecker/CMakeLists.txt
+++ b/app/presetChecker/CMakeLists.txt
@@ -9,7 +9,7 @@ include_directories(${AVTRANSCODER_SRC_PATH} ${FFMPEG_INCLUDE_DIR})
 # Add C++11 flag
 if(NOT WIN32)
 	set(CMAKE_CXX_FLAGS "-std=c++0x")
-elseif(NOT MSVC12)
+elseif(${MSVC_VERSION} LESS 1800)
 	message("C++11 not supported, will not build avPresetChecker app.")
 	return()
 endif()
diff --git a/src/AvTranscoder/option/CodecContext.hpp b/src/AvTranscoder/option/CodecContext.hpp
index 0202ebde..81de85e5 100644
--- a/src/AvTranscoder/option/CodecContext.hpp
+++ b/src/AvTranscoder/option/CodecContext.hpp
@@ -12,7 +12,7 @@ namespace avtranscoder
  * @brief Wrapper of an AVCodecContext.
  * @note The AVCodecContext is allocated and free by the class. It is not the case of the base class.
  */
-class CodecContext : public Context
+class AvExport  CodecContext : public Context
 {
 public:
 	CodecContext( int req_flags = 0 );
diff --git a/src/AvTranscoder/option/Context.hpp b/src/AvTranscoder/option/Context.hpp
index 17bce389..b804943c 100644
--- a/src/AvTranscoder/option/Context.hpp
+++ b/src/AvTranscoder/option/Context.hpp
@@ -15,7 +15,7 @@ namespace avtranscoder
  * @brief Wrapper of AVContext.
  * Can access Options through the corresponding context.
  */
-class Context
+class AvExport Context
 {
 public:
 	Context() {}