System Restore

System Restore is a component of Microsoft's Windows Me, Windows XP and Windows Vista operating systems that allows for the rolling back of system files, registry keys, installed programs, etc., to a previous state in the event of malfunctioning or failure.

The Windows Server operating system family does not include System Restore. The System Restore built into Windows XP can be installed on a Windows Server 2003 machine, although this is not supported by Microsoft.

In Windows Vista, System Restore features an improved interface and is based on Shadow Copy technology. In prior Windows versions, it was based on a file filter that watched changes for a certain set of file extensions, and then copied files before they were overwritten.The advantage of using Shadow Copy is that block-level changes in files located in any directory on the volume can be monitored and backed up regardless of their location.

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