Hi,
This is a file that is created after Speedfan is installed, more specifically by its Give I/O service which is used to retrieve values from thermal sensors. AFAIK, it's not necessary, and you can delete it. If it won't let you, boot into Safe Mode and delete it there, or try zipping it up with a zip software such as WinRAR, 7-Zip, etc, and it should delete the file.
Regards,
Patrick