%systemroot%

Dexter Sinister

Unspecified Specialist
Oct 1, 2004
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Regina, SK
Usually it means "C:\Windows," the place where the operating system files are. The % signs around it identify it as a variable name. Get a command window up (Start - Run - cmd) and type "set" without the quote marks, and you'll get a list of all the variables the system knows about. You can use them yourself in script and batch files, if you do that sort of thing.