I have an older HP DC7900 that I use for testing hard drives, memory, cards, and software. This machine is only turned on when I need to test something. I loaded Windows 7 and used the Daz loader. Ran the Win 10 upgrade. Everything was perfect. Then I switched the hard drive and loaded Windows 10 Enterprise 2015 LTSB N Privacy en-US from murphy78. Checked it out and decided it wasn't for me. Put the old hard drive back in and everything appears to be fine. Since Microsoft is keeping Windows 10 activations, on a machine basis, is this likely to cause problems down the road. I will probably put a formatted hard drive in the machine and try something different.