Microsoft has released this night an important update for Microsoft Security Essentials. This changes MSE to version 4.10.209.0. Details, what's new or changed, are not available. The links offered in Update window points to Windows 10 advertorials. And KB article 3205972 hasn't published yet. Also Pre Release-Channel doesn't offers a clue, the version downloadable is 4.8.0203.0. [Update: It seems that Microsoft has re-added the context menu to scan files and folders.]