After you've made significant modifications to the configuration of your Windows Vista computer, you should perform a Complete PC Backup of the system. Complete PC does a block-level backup of your entire system volume as a .vhd (Virtual Hard Drive) file. Note that you need a second local hard drive available to store this .vhd file.
While you can use the Backup and Restore Center in Vista to perform a Complete PC Backup of your computer, you can also do this from an elevated command prompt as follows:
wbadmin start backup –backupTarget:Z: -include:C: -quiet
where Z: is the drive letter of your backup volume.
You can also use Task Scheduler to configure this command to run on a scheduled basis (make sure you configure the task to run using admin privileges). The first time the task runs, it backs up your entire system drive as a .vhd file. On successive occurrences it updates this .vhd file.
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