As reported last week by Infosecurity, Security Essentials is a free anti-virus application for Windows-driven PCs that is planned for commercial shipment in the second half of 2009.

The application is intended as a replacement for Live OneCare, Microsoft's subscription-based service, which is about to be quietly shelved, sources suggest.

Originally code-named Morro, the free-to-use software has been described by Microsoft as offering "comprehensive protection from malware such as viruses, spyware, rootkits and trojans."

It remains unclear where the software will sit in the already crowded free IT security applications marketplace, although anecdotal evidence suggests that pay-for software from the likes of McAfee, Symantec and Trend Micro is likely to be more comprehensive.

Last November, Microsoft said that the new, no-cost offering will give the software giant the ability to protect an even greater number of consumers, especially in markets where the growth of new PC purchases is outpaced by the growth of malware.