diff --git a/uriloader/exthandler/HandlerServiceParent.cpp b/uriloader/exthandler/HandlerServiceParent.cpp
index 8f73c7cb8c8e..0796c7428b18 100644
--- a/uriloader/exthandler/HandlerServiceParent.cpp
+++ b/uriloader/exthandler/HandlerServiceParent.cpp
@@ -321,7 +321,7 @@ mozilla::ipc::IPCResult HandlerServiceParent::RecvExistsForProtocol(
     *aHandlerExists = false;
     return IPC_OK();
   }
-#if defined(XP_MACOSX)
+#if defined(XP_MACOSX) || defined(XP_WIN)
   // Check the datastore and fallback to an OS check.
   // ExternalProcotolHandlerExists() does the fallback.
   nsresult rv;
diff --git a/uriloader/exthandler/nsExternalHelperAppService.cpp b/uriloader/exthandler/nsExternalHelperAppService.cpp
index 228c6ba51be4..820f3d0af36f 100644
--- a/uriloader/exthandler/nsExternalHelperAppService.cpp
+++ b/uriloader/exthandler/nsExternalHelperAppService.cpp
@@ -638,7 +638,7 @@ static StaticRefPtr<nsExternalHelperAppService> sExtHelperAppSvcSingleton;
 already_AddRefed<nsExternalHelperAppService>
 nsExternalHelperAppService::GetSingleton() {
   if (!sExtHelperAppSvcSingleton) {
-#ifdef XP_MACOSX
+#if defined(XP_MACOSX) || defined(XP_WIN)
     if (XRE_IsParentProcess()) {
       sExtHelperAppSvcSingleton = new nsOSHelperAppService();
     } else {
@@ -646,7 +646,7 @@ nsExternalHelperAppService::GetSingleton() {
     }
 #else
     sExtHelperAppSvcSingleton = new nsOSHelperAppService();
-#endif /* XP_MACOSX */
+#endif  // defined(XP_MACOSX) || defined(XP_WIN)
     ClearOnShutdown(&sExtHelperAppSvcSingleton);
   }