Edit: ignore the rest of the message. I just found an entry in said registry key called "!Do not use this registry key". Value: "Use the SHGetFolderPath or SHGetKnownFolderPath function instead". But, if you still want to try it (backup the registry first!)...
Edit again: I just looked up those two functions. It seems this message was aimed at programmers using the registry to get the location of the shell folders. Those two functions do that, which is safer, I guess, than writing a program that noses around in your registry. Even so, continue at your own risk
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I've found in the registry, this key:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders
It contains a list of all your shell folders (Music, Documents, etc) and their respective locations.
I haven't tried it, and don't know whether it will work, but try creating a new folder called "Test" (or whatever
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). Then add a new REG_SZ into this registry key called "Test" and set the value to the path of the folder.
Next, type "shell:Test" into the Start Menu search bar thingy - with a bit of luck, it will open the Test folder. But, most likely, this won't work
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.