For many users, this can provide restore points covering the past several weeks. Old restore points are discarded in order to keep the volume's usage within the specified amount.

Moreover, the restore itself can be undone. In System Restore, the user may create a new restore point manually (as opposed to the system creating one automatically), roll back to an existing restore point, or change the System Restore configuration. An updated version of System Restore introduced by Windows Vista uses the Shadow Copy service as a backend (allowing block-level changes in files located in any directory on the volume to be monitored and backed up regardless of their location) and allows System Restore to be used from the Windows Recovery Environment in case the Windows installation no longer boots at all.

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. This does not affect personal files such as documents, music, pictures, and videos. In Windows 10, System Restore is turned off by default and must be enabled by users in order to function. First included in Windows Me, it has been included in all following desktop versions of Windows released since, excluding Windows Server. System Restore is a feature in Microsoft Windows that allows the user to revert their computer's state (including system files, installed applications, Windows Registry, and system settings) to that of a previous point in time, which can be used to recover from system malfunctions or other problems.

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Restore windows registry