Actually, I'd rather use
code:
IF @INWIN=2
  ; run this for Windows 9x only
ENDIF
IF @INWIN=1
  ; run this for Windows NT/2000/XP only
ENDIF
IF @INWIN<>1
  ; run this for (not) Windows NT/2000/XP only
ENDIF
Conditions Number 1 and 3 are lgically different conditions as in one case you want to explicitly run it only for Windows 9x whereas in condition #3 you want to run it for any computer that is not a Windows NT/2000/XP computer, which is an implicit statement to run it under Windows 9x (or anything else that is not Windows NT/2000/XP).

This will make a difference in case @INWIN at some point in the future might receive a third potential return value like @INWIN=0 or @INWIN=3 (Linux-based computer maybe?).
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