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"Windows Essentials: Other Programs - Microsoft Windows"
Windows Live Mesh is the new, upgraded form of the Microsoft Synchronization Manager, which allows files to be synced across a Microsoft network. Live Mesh upgrades and enhances the Sync Manager with new features, with the ability to sync files and folders through not only a Microsoft network or a Microsoft Windows-based computer, but also with Mac OS X computers and even with files stored in a cloud storage system, such as the Windows Live SkyDrive.
Although prior to Windows 7 has been a part of the standard Windows installation, Windows 7 has removed it in favor of additional performance, but was later bundled as part of the Windows Live Essentials suite, a collection of optional applications for Windows that include Windows Live Mail, Windows Live Writer, Windows Live Messenger, and so on. Live Mesh marries aspects from the older Windows Sync Manager with FolderShare, which Microsoft acquired as part of the Windows Live service.
Windows Live Mesh is able to sync a maximum of 200 folders, with 100,000 files within, and each file up to 40 GB in size; this is for PC-to-PC connections only, plus application settings for Internet Explorer and Microsoft Office components.