I can't comment on any Windows-specific stuff, but I observe that in neither your file-open-for-writing code, nor in the directory-making code, do you check for errors. Any error messages might give a better clue what the issue is.

open my $fh, '>', 'path to windows folder'
    or die "Can't open 'path to windows folder': $!\n";
...
mkdir $dirPath,0777
    or die "Can't make directory '$dirPath': $!\n";
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Dave.