You need to reupload the files, they're impossible to extract because two become "00x" files. You need to have something like (x) before the dot7zip.
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Because Winrar has had virus scandals before and is not completely free, not everyone uses it, but 7Zip is free and open source and more efficient. If the network you are using is not very good, .00X will be lost and cannot be decompressed due to the delay in obtaining the file name from the server. It is not recommended to use Winrar to decompress 7Z files.