%windir% is the Windows directory (I.E: C:\windows) and %systemroot% is the HD root dir (c:\)

Sorry Radu175 it seems you’ve never tried these two because the answer is wrong.
Both syntaxes do the same action, you may want to try it your self.

From the "windows script host reference" on MSDN...
 

• SYSTEMROOT System directory (for example, c:\winnt). This is the same as WINDIR.

WINDIR System directory (for example, c:\winnt). This is the same as SYSTEMROOT. [/list:u]
 
However, WINDIR is available as a system and process variable under W2K and as a process variable under Win9x, but SYSTEMROOT is a W2K process variable only.
 
 
 
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