diff --git a/dlls/wuapi/main.c b/dlls/wuapi/main.c
index c2ed95ed42b..63392b3660c 100644
--- a/dlls/wuapi/main.c
+++ b/dlls/wuapi/main.c
@@ -111,6 +111,7 @@ static const struct IClassFactoryVtbl wucf_vtbl =
 static wucf sessioncf = { { &wucf_vtbl }, UpdateSession_create };
 static wucf updatescf = { { &wucf_vtbl }, AutomaticUpdates_create };
 static wucf sysinfocf = { { &wucf_vtbl }, SystemInformation_create };
+static wucf installercf = { { &wucf_vtbl }, UpdateInstaller_create };
 
 static HINSTANCE instance;
 
@@ -146,6 +147,10 @@ HRESULT WINAPI DllGetClassObject( REFCLSID rclsid, REFIID iid, LPVOID *ppv )
     {
        cf = &sysinfocf.IClassFactory_iface;
     }
+    else if (IsEqualGUID( rclsid, &CLSID_UpdateInstaller ))
+    {
+       cf = &installercf.IClassFactory_iface;
+    }
     if (!cf) return CLASS_E_CLASSNOTAVAILABLE;
     return IClassFactory_QueryInterface( cf, iid, ppv );
 }
diff --git a/include/wuapi.idl b/include/wuapi.idl
index d1a35930841..a0a8e4359a9 100644
--- a/include/wuapi.idl
+++ b/include/wuapi.idl
@@ -1329,6 +1329,15 @@ interface ISystemInformation : IDispatch
 ]
 coclass AutomaticUpdates { interface IAutomaticUpdates; }
 
+[
+    helpstring("UpdateInstaller Class"),
+    threading(both),
+    progid("Microsoft.Update.Installer.1"),
+    vi_progid("Microsoft.Update.Installer"),
+    uuid(d2e0fe7f-d23e-48e1-93c0-6fa8cc346474)
+]
+coclass UpdateInstaller { interface IUpdateInstaller; }
+
 [
     helpstring("UpdateSession Class"),
     threading(both),