diff --git a/ext/com_dotnet/com_com.c b/ext/com_dotnet/com_com.c
index 68252daab0b..77f988c9e44 100644
--- a/ext/com_dotnet/com_com.c
+++ b/ext/com_dotnet/com_com.c
@@ -52,7 +52,7 @@ PHP_FUNCTION(com_create_instance)
 		RPC_C_AUTHN_LEVEL_DEFAULT, RPC_C_IMP_LEVEL_IMPERSONATE,
 		&authid, EOAC_NONE
 	};
-	zend_long cp = CP_ACP;
+	zend_long cp = GetACP();
 	const struct php_win32_cp *cp_it;
 
 	php_com_initialize();
diff --git a/ext/com_dotnet/com_dotnet.c b/ext/com_dotnet/com_dotnet.c
index 58002bb0f30..72e4ffc28b3 100644
--- a/ext/com_dotnet/com_dotnet.c
+++ b/ext/com_dotnet/com_dotnet.c
@@ -196,7 +196,7 @@ PHP_FUNCTION(com_dotnet_create_instance)
 	int ret = FAILURE;
 	char *where = "";
 	IUnknown *unk = NULL;
-	zend_long cp = CP_ACP;
+	zend_long cp = GetACP();
 	const struct php_win32_cp *cp_it;
 
 	php_com_initialize();