ERUNT (Emergency Recovery Utility NT) allows you to keep a complete backup of your registry and restore it when needed. The standard registry backup options that come with Windows back up most of the registry but not all of it. ERUNT however creates a complete backup set, including the Security hive and user related sections. ERUNT is easy to use and since it creates a full backup, there are no options or choices other than to select the location of the backup files. The backup set includes a small executable that will launch the registry restore if needed.

You can also used this application in dos mode. Just go to the backup path usually it is located at c:\windows\erdnt\autobackup\then the date.
This utility saves me several times especially during BSOD problem!!!
Also you can add a parameter to specify the duration of dates for the application to create a backup. Just go click start- all programs- startup then right click erunt then properties then add a parameter at the end of the target textbox with space /days:7
ex."C:\Program Files\ERUNT\AUTOBACK.EXE" %SystemRoot%\ERDNT\AutoBackup\#Date# /noconfirmdelete /noprogresswindow /days:7

Hope this help!!!

to download click the link http://www.snapfiles.com/get/erunt.html
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