diff --git a/cloudbaseinit/osutils/windows.py b/cloudbaseinit/osutils/windows.py
index 0c8d19f0..07433b69 100644
--- a/cloudbaseinit/osutils/windows.py
+++ b/cloudbaseinit/osutils/windows.py
@@ -311,9 +311,9 @@ class WindowsUtils(base.BaseOSUtils):
 
     def reboot(self):
         with privilege.acquire_privilege(win32security.SE_SHUTDOWN_NAME):
-            ret_val = advapi32.InitiateSystemShutdownW(
+            ret_val = advapi32.InitiateSystemShutdownExW(
                 0, "Cloudbase-Init reboot",
-                0, True, True)
+                0, True, True, 0)
             if not ret_val:
                 raise exception.WindowsCloudbaseInitException(
                     "Reboot failed: %r")
diff --git a/cloudbaseinit/tests/osutils/test_windows.py b/cloudbaseinit/tests/osutils/test_windows.py
index b81144a8..cf69fa28 100644
--- a/cloudbaseinit/tests/osutils/test_windows.py
+++ b/cloudbaseinit/tests/osutils/test_windows.py
@@ -101,7 +101,7 @@ class TestWindowsUtils(testutils.CloudbaseInitTestBase):
                      expected_ret_value=None):
         mock_privilege_module.acquire_privilege = mock.MagicMock()
         advapi32 = self._windll_mock.advapi32
-        advapi32.InitiateSystemShutdownW = mock.MagicMock(
+        advapi32.InitiateSystemShutdownExW = mock.MagicMock(
             return_value=ret_value)
 
         if not ret_value:
@@ -111,10 +111,10 @@ class TestWindowsUtils(testutils.CloudbaseInitTestBase):
         else:
             self._winutils.reboot()
 
-            advapi32.InitiateSystemShutdownW.assert_called_with(
+            advapi32.InitiateSystemShutdownExW.assert_called_with(
                 0,
                 "Cloudbase-Init reboot",
-                0, True, True)
+                0, True, True, 0)
         mock_privilege_module.acquire_privilege.assert_called_once_with(
             self._win32security_mock.SE_SHUTDOWN_NAME)