Why does Paragon Hard Disk Manager 16 use the Windows Product ID as the GUID for the license activation. The last 3 digits of the Windows Product ID changes each time Windows 10 is reinstalled. If I don't enter a Windows 10 product key and just have a digital license the default Product ID for Windows 10 Home is 00326-10000-00000-AA### where ### is the number that is randomly generated each time Windows 10 is reinstalled from scratch. The release license feature in the account can only be used 5 times and would be needed each time the GUID changes as a result of OS reinstallation. Using the Windows Product ID is not the best way to identify the computer as it's linked to the OS, not the hardware. The Mac version uses the hardware UUID of the Mac hardware as the GUID. The Windows Product ID would only be unique if the Windows Product Key is entered during installation otherwise use the default Product ID with only the last 3 digits different each time Windows 10 is reinstalled.