The Windows 8 and Windows 8.1 operating systems are no longer supported by Microsoft. This means that it is not safe or secure to use as it will not receive any more security patches from Microsoft. You can read more on Mocrosoft's website here:
The last version of Pirform that will install on Windows 8 or Windows 8.1 is Pirform 2018.1.1200. Future versions will require Windows 7 or Windows 10.
Any customers still using Windows 8 or Windows 8.1 should upgrade now to a more recent version of Windows.