diff --git a/appveyor.yml b/appveyor.yml
index e3b184be..a7283bb1 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -29,7 +29,7 @@ environment:
     - GENERATOR: '"Visual Studio 15 2017 Win64"'
       BUILD_TYPE: Release
       WCHAR: 'OFF'
-      BUILD_SHARED: 'OFF'
+      BUILD_SHARED: 'ON'
 build_script:
   - cmd: >-
       set
diff --git a/include/spdlog/fmt/fmt.h b/include/spdlog/fmt/fmt.h
index 0687e441..9f308ad0 100644
--- a/include/spdlog/fmt/fmt.h
+++ b/include/spdlog/fmt/fmt.h
@@ -11,9 +11,6 @@
 //
 
 #if !defined(SPDLOG_FMT_EXTERNAL)
-#if !defined(FMT_HEADER_ONLY)
-#define FMT_HEADER_ONLY
-#endif
 #ifndef FMT_USE_WINDOWS_H
 #define FMT_USE_WINDOWS_H 0
 #endif