Microsoft recently released the latest version of its free Microsoft Security Essentials (MSE) software for Windows.

"The bulk of the changes this time are under the hood," notes BetaNews' Mike Williams. "MSE’s 'Automatic Remediation' now does a better job of quarantining threats on its own, for instance, no user intervention required. And Microsoft claims scanning performance and malware detection rates have both improved on the previous build. The program can now also use the Microsoft Active Protection Service (the new name for SpyNet) to automatically report malware to Microsoft, helping the company to create new definitions and more quickly respond to new outbreaks. "

"Just a reminder about MSE’s origins: MSE was aimed first and foremost at users who either can’t or won’t pay for antivirus/anti-malware software, with the idea being that more secure Windows PCs mean less security risks for all Windows users," writes ZDNet's Mary-Jo Foley. "With MSE, there is no registration required, no trials with an expiration date or required renewals. But Microsoft does restrict the MSE download (both the beta and final) to PCs running Genuine Windows (which has been authenticated as non-pirated)."

"According to software analysis firm OPSWAT, Microsoft's Security Essentials came in at second [PDF file] for North American antivirus market share with 14.92 percent -- less than two points below the top-used antivirus software from Symantec," writes's Chris Paoli. "This last quarter saw Security Essentials overtake AVG for that second slot. However, for successful detection rates, antivirus software testing company AV-Comparatives ranked Microsoft last [PDF file] out of 15 antivirus makers for total detection rate. "