You should not call C:\WINDOWS as a hard coded path. This can lead to failure on some systems which might have Windows installed in another folder such as WINNT or another and possibly even on another drive.
According to Microsoft documentation %SystemRoot% is the preferred method of locating the installation folder however in practice it does not appear that anyone is following that directive from what I see. In either case
%SystemRoot% or %WINDIR% should return the installation location of Windows.
