Shadow copying allows the Windows file server to take a "snapshot" of files or folders at preset times. These snapshots allow you to restore previous versions of files as needed. There are a few things to remember about the use of the shadow copies or "snapshots."

The dates listed on the copies of various files will be different. Shadow copies are not intended for either short or long term storage.
The number of previous copies of a file and the length of time for those copies will be available is fluid. As a result, this is not an option for file storage. As the system keeps making shadow copies of altered information, the copies will begin to overwrite each other. Depending on the total number of altered files, etc. in a given month, there might be fewer copies listed.
In order to retrieve a deleted file using this method, it will be necessary to right click the folder or drive where the file was located. Double click the folder or drive in the list to locate the file, select it, then to copy the file back to the original location.
It is important to remember the distinctions between the "Restore" and "Copy" options. Copy allows you to make a copy of the version you select and then place it somewhere other than the original location. This is useful if you need to compare changes or when you need to restore an entire folder in order to retrieve a deleted file. Restore will overwrite the file/folder/contents with any changes you made since the date of the version you choose to restore. There is a warning when you select this option to verify that overwriting the information is what you choose.

To access the shadow copies:

Locate the file (through Windows Explorer, My Computer, etc.).
Right click the file or folder.
Left click Properties on the menu that appears.
Click the Previous Versions tab.
Left click the version of the file you would like to view, copy, or restore.
To View: Click the view button. The program associated with the file will open.
To Copy: Click the copy button. You will select a location to save the file where you can open or copy it later.
To Restore: This is not recommended. This option will overwrite the file as it currently exists with the older shadow copy. If this is the best option, when the software asks if you are sure, answer Yes.

At this time, all Windows XP and 2000 workstations on campus have this option installed. If the Previous Versions tab is not available, be sure that you are checking a server where the software is in effect. Currently department web, hold (K:\), and the GIS server is not creating the shadow copies. If you check a file or folder on your Home (H:\), Userpages, department area file storage, projects, or organization drive and the tab is not available, contact the Solution Center with the ID tag number of the computer with the problem.

This document last reviewed August 16th, 2007