diff --git a/appveyor.yml b/appveyor.yml
index ba1c221b..eeed4724 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -22,10 +22,10 @@ build_script:
 - cmake --build . --config Release
 - cd ..
 - cd ..
-- appveyor DownloadFile http://zlib.net/zlib-1.2.11.tar.gz -FileName zlib-1.2.11.tar.gz
-- 7z x zlib-1.2.11.tar.gz > NUL
-- 7z x zlib-1.2.11.tar > NUL
-- cd zlib-1.2.11
+- appveyor DownloadFile http://zlib.net/zlib-1.2.12.tar.gz -FileName zlib-1.2.12.tar.gz
+- 7z x zlib-1.2.12.tar.gz > NUL
+- 7z x zlib-1.2.12.tar > NUL
+- cd zlib-1.2.12
 - md build
 - cd build
 - cmake -G %msvc% ..
@@ -35,9 +35,9 @@ build_script:
 - cd ..
 - md build
 - cd build
-- cmake -G %msvc% -DGTEST_LIBRARY=%APPVEYOR_BUILD_FOLDER%\googletest-release-1.7.0\build\Release\gtest.lib -DGTEST_MAIN_LIBRARY=%APPVEYOR_BUILD_FOLDER%\googletest-release-1.7.0\build\Release\gtest_main.lib -DGTEST_INCLUDE_DIR=%APPVEYOR_BUILD_FOLDER%\googletest-release-1.7.0\include -DZLIB_LIBRARY=%APPVEYOR_BUILD_FOLDER%\zlib-1.2.11\build\Release\zlib.lib -DZLIB_INCLUDE_DIR=%APPVEYOR_BUILD_FOLDER%\zlib-1.2.11 -DCMAKE_CXX_FLAGS='"/D_VARIADIC_MAX=10 /EHsc"' ..
+- cmake -G %msvc% -DGTEST_LIBRARY=%APPVEYOR_BUILD_FOLDER%\googletest-release-1.7.0\build\Release\gtest.lib -DGTEST_MAIN_LIBRARY=%APPVEYOR_BUILD_FOLDER%\googletest-release-1.7.0\build\Release\gtest_main.lib -DGTEST_INCLUDE_DIR=%APPVEYOR_BUILD_FOLDER%\googletest-release-1.7.0\include -DZLIB_LIBRARY=%APPVEYOR_BUILD_FOLDER%\zlib-1.2.12\build\Release\zlib.lib -DZLIB_INCLUDE_DIR=%APPVEYOR_BUILD_FOLDER%\zlib-1.2.12 -DCMAKE_CXX_FLAGS='"/D_VARIADIC_MAX=10 /EHsc"' ..
 - cmake --build . --config Release -v
 
 test_script:
-- set PATH=%PATH%;%APPVEYOR_BUILD_FOLDER%\googletest-release-1.7.0\build\Release;%APPVEYOR_BUILD_FOLDER%\zlib-1.2.11\build\Release;%APPVEYOR_BUILD_FOLDER%\build\release
+- set PATH=%PATH%;%APPVEYOR_BUILD_FOLDER%\googletest-release-1.7.0\build\Release;%APPVEYOR_BUILD_FOLDER%\zlib-1.2.12\build\Release;%APPVEYOR_BUILD_FOLDER%\build\release
 - ctest -V