The SP2Torrent.com web site was set up by file sharing activist group Downhill Battle to showcase how peer-to-peer networking can distribute very large files over the internet as an alternative to downloading from a centralised server.
However lawyers for the Redmond Behemoth cited the Digital Millennium Copyright Act (DMCA) and served takedown notices on the file sharing website and another that had a link to a torrent file on another server.
In a statement on its website, Downhill Battle said it thought it had made a "pretty good case" for the role file sharing could make in distributing major software releases.
"The site has been a huge success in demonstrating p2p technology– we've had over 100,000 visitors in the past few days and some good press coverage," it added.
Microsoft was unable to comment at the time of going to press.
Seperately, the company released a list of more than 40 applications that conflict with the new Service Pack 2. The details embarrassingly include some of the company's own applications.
The list can be found here: http://support.microsoft.com/default.aspx?kbid=842242