Toggling the Peer-to-Peer Transfer feature may have a significant impact on your ability to install or patch Blizzard® games. While traditional downloads use a single source, peer-to-peer transfers allow users to gather data from other users, which often improves download speed. This option can be found in the Preferences > Downloader Preferences for the Blizzard Downloader and Blizzard games.
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Article ID: 7300080