Restart explorer the "official" graceful way

[DartVanya]

No description provided.

[dmex]

Which OS are these values from?

[DartVanya]

It's Vista+
https://stackoverflow.com/questions/5689904/gracefully-exit-explorer-programmatically
ExplorerPatcher uses same method
https://github.com/valinet/ExplorerPatcher/blob/80b5d73d22bba2c7acc286c998231463de2c8fdc/ExplorerPatcher/utility.h#L479

[dmex]

We can't send private window messages since the identifiers can change. The menu this references was removed on Windows 11.

[dmex]

Here's a fully documented and official method for restarting the Explorer process:

BOOL CALLBACK EnumWindowCallback(
    _In_ HWND WindowHandle,
    _In_ LPARAM Context
    )
{
    ULONG processId = 0;

    GetWindowThreadProcessId(WindowHandle, &processId);

    if (processId == (ULONG)Context && IsWindowVisible(WindowHandle))
    {
        ULONG_PTR result = 0;

        if (SendMessageTimeout(
            WindowHandle,
            WM_QUERYENDSESSION,
            0,
            ENDSESSION_CLOSEAPP,
            SMTO_ABORTIFHUNG | SMTO_BLOCK | SMTO_ERRORONEXIT,
            5000,
            &result
            ))
        {
            if (result)
            {
                SendMessageTimeout(
                    WindowHandle,
                    WM_ENDSESSION,
                    TRUE,
                    ENDSESSION_LOGOFF,
                    SMTO_ABORTIFHUNG | SMTO_BLOCK | SMTO_ERRORONEXIT,
                    5000,
                    &result
                    );
            }
        }
    }

    return TRUE;
}

VOID CloseExplorer()
{
    ULONG processId = 0;

    GetWindowThreadProcessId(GetShellWindow(), &processId);

    EnumWindows(EnumWindowCallback, (LPARAM)processId);
}

The Explorer process and desktop shell cleanup and exit cleanly. If there are multiple explorer.exe processes then you have to send these message to both processes. This code only sends the message to the shell window as an example showing it cleanup and exit successfully.

These messages and functions are documented and supported by Microsoft:
https://learn.microsoft.com/en-us/windows/win32/shutdown/wm-queryendsession
https://learn.microsoft.com/en-us/windows/win32/shutdown/wm-endsession
https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-sendmessagetimeoutw