How to change my documents folder via registry?

Archived from groups: microsoft.public.windowsxp.customize (More info?)

My network logon script changes the My Documents folder to a default
location every time I log on. That drive is full, so I'd like to
redirect the location to another drive.

I can do it manually by right clicking on My Documents on the desktop.
However, I'd like to set up a registry update file that I can call in a
startup bat file (since it changes back each logon).

I tried a file that changes the values in both:
HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell
Folders - Personal
HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders -
Personal

The changes take in the registry, but the folder doesn't move. How can
I get this to work?

-MVL