Kuro5hin: "Several days ago, two files containing Microsoft source code began circulating on the Internet. One contains a majority of the NT4 source code: this is not discussed here. The other contains a fraction of the Windows 2000 source code, reportedly about 15% of the total. This includes some networking code including winsock and inet; as well as some shell code. Some other familiar items include the event log, and some of the default screensavers.
The timestamps on the files generally say 25 July 2000. The source is contained in a Zip file of size 213,748,207 bytes, named windows_2000_source_code.zip, which has been widely circulated on P2P networks. Some dummy files of similar size, containing just strings of zeroes, have also circulated.
There has been some speculation that while the bulk of the source is genuine, some of the comments have been tampered with to embarrass Microsoft. This is difficult to disprove, but I find it implausible. The embarrassing comments occur on thousands of lines, in realistic places. Furthermore, if someone had done that, it would have been easy to make the comments far more incriminating."