The problem is that Win32API::File means different things when it is quoted and when it is a bareword. See require.

A better approach might be to use eval and check the value of $@:

    eval {require Win32API::File};

    if (not $@) {
        my @drv = map {s/\\$//;lc} Win32API::File::getLogicalDrives();
        print @drv;
    }
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--
John.

"Strange things happen when you're not around" - Billy Bragg