It appears to be a limitation that won't let you change to that location again if apps were already installed on it unless you delete them first.

It's saying that it can't change storage locations to install new apps on D since you already have apps installed on D without deleting the already installed apps on D first. :(

You could use the tutorial below to make sure that new apps will be installed where you like.

https://www.tenforums.com/tutorials/6422-apps-save-location-change-windows-10-a.html

Hello clayto, :)

Store apps are installed to the hidden protected "C:\Program Files\WindowsApps" folder by default.