Falha instalação dual boot

wjt · August 14, 2020, 9:37am

Yes, it does look like the installer is incorrectly detecting a UEFI system. But the logic we use is very simple and is documented in Microsoft’s own documentation.

github.com

endlessm/rufus/blob/04b5f55f74c46e963f3bd82933f9010dbd9efe21/endless/src/endless/EndlessUsbToolDlg.cpp#L5636-L5645


bool CEndlessUsbToolDlg::IsLegacyBIOSBoot()
{
	FUNCTION_ENTER;
	// From https://msdn.microsoft.com/en-us/library/windows/desktop/ms724325(v=vs.85).aspx
	// On a legacy BIOS-based system, or on a system that supports both legacy BIOS and UEFI where Windows was installed using legacy BIOS,
	// the function will fail with ERROR_INVALID_FUNCTION. On a UEFI-based system, the function will fail with an error specific to the firmware,
	// such as ERROR_NOACCESS, to indicate that the dummy GUID namespace does not exist.
	DWORD result = GetFirmwareEnvironmentVariable(L"", L"{00000000-0000-0000-0000-000000000000}", NULL, 0);
	return result == 0 && GetLastError() == ERROR_INVALID_FUNCTION;
}

Unfortunately there isn’t a good way to work around this misdetection at the moment.