If you are downloading files regularly from the Usenet, you may have noticed that some downloads do not complete anymore. Transfers work in pretty much the same way as downloading files via P2P connections, and if a file is listed as complete by the Usenet server you are using, it should download just fine to your system as well, right?
It should be clear that partial file downloads will be broken on the system, but you have PAR2 files for that which you can use to recover the full file. You can use Par2 files to recovery any download, provided that the Par2 blocks are of the same size or larger than the incomplete, corrupt or missing blocks of the downloaded file.
But this article is not about incomplete or corrupt uploads, it is about a trend that has reached the Usenet. I'm talking about DMCA requests to pull down data from servers. Rights-holders use DCMA requests to ask companies to pull data from the Internet. This can happen using automation or manually, but we have seen in the past that the process is not 100% fool proof and that legit files may be pulled due to requests.
You may know that from Google Search where results may have been removed due to these requests. The same requests are sent to file hosting providers, websites, blogs, and now Usenet Providers.
The provider pulls the files from the server after verifying that the DCMA request is legitimate. The result is that while the file is not available anymore on the server, it is still listed in the headers that you retrieve when you update a group that you download files from. The file is listed there as any other complete file, and you will only notice that it is not when you try to download it to your computer.
Depending on when you try to download the file, your download may not start at all, or may stop at any point. This usually happens when the files get removed while you are downloading or while some parts are still available on cache servers or content distribution networks.
You can't download that file anymore once it has been pulled by the Usenet provider. You sometimes may be able to recover the files using par files, but only if you were able to download the file partially to your system.
Ghacks is a technology news blog that was founded in 2005 by Martin Brinkmann. It has since then become one of the most popular tech news sites on the Internet with five authors and regular contributions from freelance writers.