diff --git a/reactos/services/umpnpmgr/umpnpmgr.c b/reactos/services/umpnpmgr/umpnpmgr.c
index c243c7e5fa1..b6d6e9df290 100644
--- a/reactos/services/umpnpmgr/umpnpmgr.c
+++ b/reactos/services/umpnpmgr/umpnpmgr.c
@@ -875,7 +875,7 @@ PNP_RequestEjectPC(handle_t BindingHandle)
     return ret;
 }
 
-typedef BOOL (*PDEV_INSTALL_W)(HWND, HINSTANCE, LPCWSTR, INT);
+typedef BOOL (WINAPI *PDEV_INSTALL_W)(HWND, HINSTANCE, LPCWSTR, INT);
 
 static BOOL
 InstallDevice(PCWSTR DeviceInstance)