Windows environment variables

["Sánchez Sanz, Javier" <jssanz () indra es>]

Hello,
I need to set and remove system or user environment variables at Windows 2000 or XP. But I need to do it by 'hand', I 
mean, with some command, not using the Windows GUI. Does anyone how to do this? If I set variables at the command 
prompt, they only last during the DOS console is open, and what I need is that they are available during the user 
session. I was looking even the registry but I don't found anything.
What I found was SetX, a reource kit from Microsoft, but it only sets the variables, and I cannot remove them.

Many thanks

Javi
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