Welcome to another screencast from the Vista Product guide on Shadow Copy.

Okay so I know all of you know the fundamental difference between SAVE and SAVE AS. However, how many of you wanted to do a SAVE AS, and you “accidentally” clicked on SAVE. It could have been a cat, small child or a breeze that made your hand click on save and not save as, I know it has to be an accident because you never consciously would make that mistake.  :-)  

However, the fact is that the part of the document you wanted is now gone.  The question becomes, now how do I recover the file. You could restore it from a backup set. However this can cause problems on how recent you’re backup data is or even if you have backed up the system. How many back up your user’s desktops on a regular basis?

Well guess what,  Shadow Copy in Windows Vista is here to help. Shadow Copy is a fantastic resource for people to help save data on their systems from a point-in-time copy of the file. The files can be recovered very quickly by right clicking on the file or even folder and selecting the previous version that you would like to recover the file.

How do you recover files and folders? 

Okay, so you have had the accident, how do you recover the data? This is very easy; you can either right click on the file and click on previous versions or go to the properties of the file and select the previous versions tab. By the way the process will work either for individual files or folders. You will see the list of restore points to choose from for that file and you will have 3 choices:

  1. Open: This will open a read-only copy of the file to verify if this is the file you want to bring back. You can also copy and paste between this file and your original. This is really handy if you have made changes and need to bring back information you accidentally deleted.
  2. Copy: This will allow you to restore a copy of the file you chose to a different location. This is great if you want to do a side-by-side comparison.
  3. Restore: This will restore the file in the original location, if you want to restore in a different location use the copy option.

How does it work?

Shadow copy is automatically turned on in Windows Vista and can be seen in the system properties. The shadow copies are created on a regular basis, during the creation of restore points. The restore points are created on a regular basis and typically when you install an application or windows update or event a driver. You can also create the restore points manually by selecting the system protection tab and clicking Create.

The great thing about these copies is that only the incremental changes are saved. This helps dramatically cut down on hard drive bloat. However, it is important to note that restore points are saved until the hard disk space System Restore reserves is filled up. As new restore points are created, old ones are deleted. The default space reserved for shadow copies is 15% of the volume size.

With the command-line tool vssadmin.exe you can change the size of this reserved space. To run any of the vssadmin.exe commands you need to run and administrative level command prompt. A command to set the size to 900MB may look like this:

vssadmin Resize ShadowStorage /For=C: /On=D: /MaxSize=900MB

This handy command will show you how much storage is currently used:

vssadmin list shadowStorage

Watch the Screencast here:

Screencast on Windows Vista Shadow Copy

Some additional comments:

As fantastic as this feature is, it does not replace the need to do regular backups. You still need to create regular backups to protect your system. Shadow copies are not created every time you change the file and remember these are stored in the system restore points and those are stored on a first-in first-off basis and that is limited to the space you reserved for the restore points.

Very Important note:

The Shadow Copy feature is available only in the Business, Enterprise, and Ultimate editions of Windows Vista.

Additional Information:

Please let me know what you think and comment if there are additional screencasts you want to see.