Shadow copy is a service that was first build into Windows 2003 Server and provided the same service as Mac users now enjoy with Time Machine many years before Apple ‘invented’ it, it provides a way of accessing file that have been changed or delete, often at multiple different times due to the way Shadow Copies are setup to collect changes every 12 hours.
This can be really worth while if you’ve ever been caught accidentally saving over a document or erasing a folder, as you can look thought the folder at in any of it’s saved states and either restore or copy the contents to a safe place.
The service works on the server and client pc can then be used to access the folder cache with the properties menu, and the previous version tab. This is fantastic because it puts the power back into the users hands, without the need of any server administator’s assistance.
Unlike the other Windows Server, the Windows Home Server, Shadow Copy needs to be enabled within a remote desktop session, by right clicking on the drive letter (normally D:) and selecting the Shadow Copy tab, then enable. This will setup your server to take a snapshot every twelve hours. The space this service uses won’t be reported to windows and doesn’t have an detrimental effect on performance, but can save you bacon on those rare occasions.
You may want to change some of the default settings if you are just using your Windows Home Server for private use, I suggest removing one of the snap shots to make it once every 24 hours and including Saturday and Sunday in the schedule.