diff --git a/dll/win32/newdev/newdev.c b/dll/win32/newdev/newdev.c
index 1b30c96dd51..960f75212d3 100644
--- a/dll/win32/newdev/newdev.c
+++ b/dll/win32/newdev/newdev.c
@@ -807,17 +807,19 @@ cleanup:
 
 BOOL
 WINAPI
-InstallDevInst(
+InstallDevInstEx(
     IN HWND hWndParent,
     IN LPCWSTR InstanceId,
     IN BOOL bUpdate,
-    OUT LPDWORD lpReboot)
+    OUT LPDWORD lpReboot,
+    IN DWORD Unknown)
 {
     PDEVINSTDATA DevInstData = NULL;
     BOOL ret;
     BOOL retval = FALSE;
 
-    TRACE("InstllDevInst(%p, %s, %d, %p)\n", hWndParent, debugstr_w(InstanceId), bUpdate, lpReboot);
+    TRACE("InstllDevInstEx(%p, %s, %d, %p, %lx)\n",
+          hWndParent, debugstr_w(InstanceId), bUpdate, lpReboot, Unknown);
 
     DevInstData = HeapAlloc(GetProcessHeap(), 0, sizeof(DEVINSTDATA));
     if (!DevInstData)
@@ -916,6 +918,21 @@ cleanup:
 }
 
 
+/*
+ * @implemented
+ */
+BOOL
+WINAPI
+InstallDevInst(
+    IN HWND hWndParent,
+    IN LPCWSTR InstanceId,
+    IN BOOL bUpdate,
+    OUT LPDWORD lpReboot)
+{
+    return InstallDevInstEx(hWndParent, InstanceId, bUpdate, lpReboot, 0);
+}
+
+
 /*
 * @implemented
 */
diff --git a/dll/win32/newdev/newdev.spec b/dll/win32/newdev/newdev.spec
index 56e3d1b4ea9..58af6c41714 100644
--- a/dll/win32/newdev/newdev.spec
+++ b/dll/win32/newdev/newdev.spec
@@ -1,7 +1,7 @@
 @ stdcall ClientSideInstallW(ptr ptr wstr long)
 @ stdcall DevInstallW(ptr ptr wstr long)
 @ stdcall InstallDevInst(ptr wstr long ptr)
-@ stub InstallDevInstEx
+@ stdcall InstallDevInstEx(ptr wstr long ptr long)
 @ stdcall InstallNewDevice(ptr ptr ptr)
 @ stub InstallSelectedDevice
 @ stdcall InstallSelectedDriverW(ptr ptr wstr long ptr)
diff --git a/sdk/include/reactos/dll/newdevp.h b/sdk/include/reactos/dll/newdevp.h
index 5ddcee203be..4967996a24c 100644
--- a/sdk/include/reactos/dll/newdevp.h
+++ b/sdk/include/reactos/dll/newdevp.h
@@ -28,6 +28,15 @@ InstallDevInst(
     IN BOOL bUpdate,
     OUT LPDWORD lpReboot);
 
+BOOL
+WINAPI
+InstallDevInstEx(
+    IN HWND hWndParent,
+    IN LPCWSTR InstanceId,
+    IN BOOL bUpdate,
+    OUT LPDWORD lpReboot,
+    IN DWORD Unknown);
+
 #ifdef __cplusplus
 }
 #endif