Can't reset password on Windows 8 PC


I have tried, in vain, to reset my windows password on my windows 8 laptop using the How to geek “How to Reset your forgotten windows password the easy way” “Simple Trick” method. The problem is that when booting from a freshly created window 8 install CD, I cannot 1. Copy the sethc.exe file to the root directory, 2. copy cmd.exe over sethc.exe. in both instances I get “The file cannot be accessed by the system”.

I removed the Hard Drive and connected it via a USB adaptor to my Windows 10 PC. In this configuration I can copy the sethc.exe file but I get “Access Denied” when invoking copy cmd.exe sethc.exe.