1, use nyllovers link. you should download the 32bit version that will surely work on your windows (on any windows).
2, when it's downloaded start -double left mouse click on it- the downloaded exe.
little install window will show up, click "install" button when it's done "finish" button
3, now find the file you want to extract, right mouse click on the file. little menu will pop up search for "7-zip" row, left mouse click on it. another little menu will show up on that search for "Extract to ####", left mouse click on it and you are done.
some comments:
- "####" equals with the foldername which will be the target folder of your extract. the folder name will be equal with the rar name.
- if you have multiple files like: pack.part1.rar, pack.part2.rar,... etc. repeat the steps just with the "part1" file. the extractor will know they belong together.
ps: my english knowledge is not that good to make such a big description. i hope i did't do any great grammatical errors. thanks google translator

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