diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8fcd0f234..bf22d2576 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -71,7 +71,7 @@ if(MSVC)
     # allow disabling of internally built OpenSSL# (see below for details)
     # if POCO pre-built OpenSSL directory is found, and POCO_DISABLE_INTERNAL_OPENSSL=OFF,
     # the internal OpenSSL build will be used
-    option(POCO_DISABLE_INTERNAL_OPENSSL "Disable internal OpensSSL binaries use" OFF)
+    option(POCO_DISABLE_INTERNAL_OPENSSL "Disable internal OpensSSL binaries use" ON)
 
     if((NOT POCO_DISABLE_INTERNAL_OPENSSL) AND (ENABLE_NETSSL OR ENABLE_CRYPTO OR (ENABLE_DATA_MYSQL AND MINGW)))
       include(UseEmbeddedOpenSSL)
diff --git a/Foundation/include/Poco/Config.h b/Foundation/include/Poco/Config.h
index 24ea1aa0a..dc23f218a 100644
--- a/Foundation/include/Poco/Config.h
+++ b/Foundation/include/Poco/Config.h
@@ -182,7 +182,9 @@
 //   empty or other value:
 //     Do not link any OpenSSL libraries automatically. You will have to edit the
 //     Visual C++ project files for Crypto and NetSSL_OpenSSL.
-#define POCO_EXTERNAL_OPENSSL POCO_EXTERNAL_OPENSSL_SLPRO
+#ifndef POCO_EXTERNAL_OPENSSL
+	#define POCO_EXTERNAL_OPENSSL POCO_EXTERNAL_OPENSSL_SLPRO
+#endif
 
 
 // Define to prevent changing the suffix for shared libraries