File backups with previous versions in Windows Vista and Windows 7
Windows Vista and Windows 7 introduced a new data file backup called "previous versions" that is part of System Protection. Its use is described here.
New in Windows 7
Prior to Windows Vista, the system service called System Restore made backup snapshots of system and program files but omitted personal and data files. Beginning with Vista , System Restore was expanded into what is known as System Protection and the monitoring of data files by a service called Volume Shadow Copy was incorporated. The individual file backups are known as "previous versions". Unfortunately, Microsoft chose to limit the "previous versions" feature to the Vista Business, Enterprise, and Ultimate editions and keep it inaccessible in Vista Home Premium. (But see below for a way around this restriction.) However, in Windows 7, the Home Premium edition also contains access to previous versions of files.
Accessing previous versions in Windows Vista and Windows 7
Whenever System Protection creates a restore point for a monitored volume, it makes copies of any data files or folders that have been changed since the last restore point. To see the various file or folder versions, right-click on a file or folder and select "Restore previous versions" from the context menu. A dialog box showing all the previous versions of the selected file or folder will open. An example for a folder called "PDFs" is shown below.
There are three buttons that allow for various operations with a selected previous version. Clicking the button "Open" will display a selected entry. Clicking "Copy" will allow you to create a copy of a particular version and save it in a different location. Clicking "Restore" will replace the present file or folder contents with those of the selected version.
Restoring a previous version of a file
As is shown in the next figure, select the previous version to be restored and click "Restore". As shown below, a dialog box will open asking for confirmation. Click "Restore"
Restore Point versions of a file will only be shown if it has been altered since the last Restore Point was created. If no previous versions are listed, open and save the file. This will cause Windows to list any Restore Point versions.
How to access previous versions in Windows Vista Home Premium
Although the shadow copy service creates previous versions of personal files in Vista Home Premium, the Microsoft marketing types tried to squeeze the home user into buying a more expensive version by making the previous versions inaccessible. However, a free utility is available called ShadowExplorer that allows Home Premium users to browse the shadow copies.