diff --git a/appveyor.yml b/appveyor.yml
index 75452e29ea..9719a8ed34 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -54,7 +54,7 @@ for:
     - mkdir \usr\local\include
     - mkdir \usr\local\lib
     - curl -fsSL -o zlib%zlib_version:.=%.zip --retry 10 https://zlib.net/zlib%zlib_version:.=%.zip
-    - 7z x -o%APPVEYOR_BUILD_FOLDER%\ext\zlib zlib%zlib_version:.=%.zip
+    - 7z x -aoa -o%APPVEYOR_BUILD_FOLDER%\ext\zlib zlib%zlib_version:.=%.zip
     - for %%I in (%OPENSSL_DIR%\*.dll) do mklink /h \usr\local\bin\%%~nxI %%I
     - attrib +r /s /d
     - mkdir %Platform%-mswin_%vs%