If, like me, you’re fascinated by some of the marvellous photos that appear on Windows 10's lock screen, you may want to save them permanently on your computer. I’ve found various very technical explanations of how to do this, but this is my simplified guide.
Begin by making hidden folders visible: open an Explorer window and select Show Hidden items from the View tab.
Navigate to <youruserprofile>\AppData\Local\Packages\Microsoft.Windows.ContentDeliveryManager_cw5n1h2txyewy\LocalState\Assets
ON NO ACCOUNT MAKE ANY CHANGES TO THIS FOLDER
Copy the files in this folder to an easily located folder elsewhere on your computer. I’ve created a dedicated Lockscreen folder in my Pictures.
In the Explorer window for the new folder (NOT the Assets folder), open a command prompt as an administrator from the File menu.
Run the following command to add a .jpg extension to all of the files you just copied: ren *.* *.jpg
The result will be a collection of images, plus assorted other files that you can delete. The photos used by the lock screen change regularly, so you may want to repeat this process from time to time, to add new ones to your collection. Act quickly to save a copy of any images you particularly like – the Assets folder changes regularly. [If you’ve wondered why your data usage has climbed since you upgraded to Windows 10, the glorious lock screen images could be part of the explanation, though only to the tune of a few MB per week.]
WARNING: If you decide to do this, please be very careful not to make any changes to the Assets folder located using Stage 2 above – otherwise you could ##~## up your computer good and proper.