You don't need this (its to demo the Windows 10 features)...
I found this snippet on the Microsoft site:
So if you wish to delete this Retail Demo and save disk space, use the built-in Disk Cleanup utility. This will clear 100MB of disk space!
Commenters say: You cannot simply use Windows Disk Cleanup to delete the Retail Demo Offline Content. It requires a password. The password of Retail Demo Admin account is trs10.
Hope this helps,
"NOTE: This post is only meant for information purposes, and we do not advice you to turn on or try this retail demo mode as it will delete all your user settings and personal content."
This is good to know... Anyone know a way to safely delete this through the registry itself?