Use Drive Mirroring for Instant Backup in Windows 7
Even with the best backup solution, a hard drive crash means you’ll lose a few hours of work. By enabling drive mirroring in Windows 7, you’ll always have an up-to-date copy of your data.
Windows 7’s mirroring – which is only available in Professional, Enterprise, and Ultimate editions – is a software implementation of RAID 1, which means that two or more disks are holding the exact same data. The files are constantly kept in sync, so that if one of the disks fails, you won’t lose any data.
Mirroring an Existing Drive
Click on the start button and type partitions in the search box. Click on the Create and format hard disk partitions entry that shows up.
Alternatively, if you’ve disabled the search box, press Win+R to open the Run window and type in:
diskmgmt.msc
The Disk Management window will appear. We’ve got a small disk, labeled OldData, that we want to mirror in a second disk of the same size.
Note: The disk that you will use to mirror the existing disk must be unallocated. If it is not, then right-click on it and select Delete Volume… to mark it as unallocated. This will destroy any data on that drive.
Right-click on the existing disk that you want to mirror. Select Add Mirror
Select the disk that you want to use to mirror the existing disk’s data and press Add Mirror.
You will be warned that this process will change the existing disk from basic to dynamic. Note that this process will not delete any data on the disk.
The new disk will be marked as a mirror, and it will starting copying data from the existing drive to the new one.
Eventually the drives will be synced up (it can take a while), and any data added to the E: drive will exist on both physical hard drives.