Hands off our code, warns Microsoft

Microsoft has issued letters warning people who have downloaded its leaked source code that such actions are "in violation of the law".

It has also "instituted the use of alerts" on several peer-to-peer clients where such illegal sharing of the source code has taken place.

In a statement the company said: "These alerts are designed to inform any user who conducts specific searches on these networks to locate and download the source code that such activity is illegal."

Microsoft said its source code is both copyrighted and protected as a trade secret.

"As such, it is illegal to post it, make it available to others, download it or use it. Microsoft will take all appropriate legal actions to protect its intellectual property," the company warned.

"These actions include communicating both directly and indirectly with those who possess or seek to possess, post, download or share the illegally disclosed source code."

Microsoft is working closely with the FBI and other law enforcement authorities on the matter.

Security firms have warned that the code leak could result in increased hacking activity.