--- a/accessible/src/windows/msaa/ServiceProvider.h
+++ b/accessible/src/windows/msaa/ServiceProvider.h
@@ -10,6 +10,7 @@
 #include <servprov.h>
 
 #include "AccessibleWrap.h"
+#include "IUnknownImpl.h"
 
 namespace mozilla {
 namespace a11y {
@@ -17,7 +18,7 @@
 class ServiceProvider MOZ_FINAL : public IServiceProvider
 {
 public:
-  ServiceProvider(AccessibleWrap* aAcc) : mRefCnt(0), mAccessible(aAcc) {}
+  ServiceProvider(AccessibleWrap* aAcc) : mAccessible(aAcc) {}
   ~ServiceProvider() {}
 
   DECL_IUNKNOWN