diff --git a/Modules/clinic/posixmodule.c.h b/Modules/clinic/posixmodule.c.h
index 00a4f6009186af9..1f7e414b2dfe48f 100644
--- a/Modules/clinic/posixmodule.c.h
+++ b/Modules/clinic/posixmodule.c.h
@@ -1851,7 +1851,7 @@ os_listdrives(PyObject *module, PyObject *Py_UNUSED(ignored))
 
 #endif /* (defined(MS_WINDOWS_DESKTOP) || defined(MS_WINDOWS_SYSTEM)) */
 
-#if (defined(MS_WINDOWS_APP) || defined(MS_WINDOWS_SYSTEM))
+#if (defined(MS_WINDOWS_DESKTOP) || defined(MS_WINDOWS_SYSTEM))
 
 PyDoc_STRVAR(os_listvolumes__doc__,
 "listvolumes($module, /)\n"
@@ -1873,7 +1873,7 @@ os_listvolumes(PyObject *module, PyObject *Py_UNUSED(ignored))
     return os_listvolumes_impl(module);
 }
 
-#endif /* (defined(MS_WINDOWS_APP) || defined(MS_WINDOWS_SYSTEM)) */
+#endif /* (defined(MS_WINDOWS_DESKTOP) || defined(MS_WINDOWS_SYSTEM)) */
 
 #if (defined(MS_WINDOWS_DESKTOP) || defined(MS_WINDOWS_SYSTEM))
 
@@ -13733,4 +13733,4 @@ os__emscripten_log(PyObject *module, PyObject *const *args, Py_ssize_t nargs, Py
 #ifndef OS__EMSCRIPTEN_LOG_METHODDEF
     #define OS__EMSCRIPTEN_LOG_METHODDEF
 #endif /* !defined(OS__EMSCRIPTEN_LOG_METHODDEF) */
-/*[clinic end generated code: output=250ea2e34fdd133f input=a9049054013a1b77]*/
+/*[clinic end generated code: output=d81494ceb6ce44ed input=a9049054013a1b77]*/
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 57db175336702e2..8167f7fbacff5bd 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -5197,7 +5197,7 @@ os_listdrives_impl(PyObject *module)
 
 #endif /* MS_WINDOWS_DESKTOP || MS_WINDOWS_SYSTEM */
 
-#if defined(MS_WINDOWS_APP) || defined(MS_WINDOWS_SYSTEM)
+#if defined(MS_WINDOWS_DESKTOP) || defined(MS_WINDOWS_SYSTEM)
 
 /*[clinic input]
 os.listvolumes
@@ -5260,7 +5260,7 @@ os_listvolumes_impl(PyObject *module)
     return result;
 }
 
-#endif /* MS_WINDOWS_APP || MS_WINDOWS_SYSTEM */
+#endif /* MS_WINDOWS_DESKTOP || MS_WINDOWS_SYSTEM */
 
 #if defined(MS_WINDOWS_DESKTOP) || defined(MS_WINDOWS_SYSTEM)
 
@@ -9933,6 +9933,7 @@ os_setpgrp_impl(PyObject *module)
 #include <winternl.h>
 #include <ProcessSnapshot.h>
 
+#ifdef MS_WINDOWS_DESKTOP
 // The structure definition in winternl.h may be incomplete.
 // This structure is the full version from the MSDN documentation.
 typedef struct _PROCESS_BASIC_INFORMATION_FULL {
@@ -10005,6 +10006,7 @@ win32_getppid_fast(void)
     cached_ppid = (ULONG) basic_information.InheritedFromUniqueProcessId;
     return cached_ppid;
 }
+#endif // MS_WINDOWS_DESKTOP
 
 static PyObject*
 win32_getppid(void)
@@ -10013,12 +10015,13 @@ win32_getppid(void)
     PyObject* result = NULL;
     HANDLE process = GetCurrentProcess();
     HPSS snapshot = NULL;
-    ULONG pid;
 
-    pid = win32_getppid_fast();
+#ifdef MS_WINDOWS_DESKTOP
+    ULONG pid = win32_getppid_fast();
     if (pid != 0) {
         return PyLong_FromUnsignedLong(pid);
     }
+#endif
 
     // If failure occurs in win32_getppid_fast(), fall back to using the PSS API.
 
@@ -15227,6 +15230,7 @@ os_abort_impl(PyObject *module)
 }
 
 #ifdef MS_WINDOWS
+#ifdef MS_WINDOWS_DESKTOP
 /* Grab ShellExecute dynamically from shell32 */
 static int has_ShellExecute = -1;
 static HINSTANCE (CALLBACK *Py_ShellExecuteW)(HWND, LPCWSTR, LPCWSTR, LPCWSTR,
@@ -15255,6 +15259,7 @@ check_ShellExecute(void)
     }
     return has_ShellExecute;
 }
+#endif // MS_WINDOWS_DESKTOP
 
 
 /*[clinic input]
@@ -15299,6 +15304,9 @@ os_startfile_impl(PyObject *module, path_t *filepath,
                   path_t *cwd, int show_cmd)
 /*[clinic end generated code: output=1c6f2f3340e31ffa input=8248997b80669622]*/
 {
+#if defined(MS_WINDOWS_APP) && !defined(MS_WINDOWS_DESKTOP)
+    return PyErr_Format(PyExc_NotImplementedError, "startfile not available on UWP");
+#else
     HINSTANCE rc;
 
     if(!check_ShellExecute()) {
@@ -15327,6 +15335,7 @@ os_startfile_impl(PyObject *module, path_t *filepath,
         return NULL;
     }
     Py_RETURN_NONE;
+#endif
 }
 #endif /* MS_WINDOWS */