One person who posted a huge 43GB torrent file claimed to have leaked Windows XP source code. According to the claim, the source code had already been in the hands of hackers for years. A torrent file uploaded to 4chan. Source codes of Windows 2000, Windows CE, MS DOS, Windows Embedded and Windows NT are also included in the leaked data.
If you don’t want to download whole file. There is also a 2.9 GB zip file that contains only the source code for Windows XP and Windows Server 2003. Microsoft hasn’t commented on this subject yet. Although , support for XP ended in 2014, there are still users who still are using this operating system.