Thanks to http://www.sevenforums.com/tutorials/48829-offline-files-enable-disable-use.html

When you make a network file, or all files in a network folder, available offline, Windows creates a copy of the file or folder on your computer. This is called an offline file. The next time you disconnect from the network, you’ll still be able to open, modify, and save the file the same way you would if you were still connected. And when you do connect to the network again, Windows will automatically sync the offline file on your computer with the corresponding file on the network to update it.
This tutorial will show you how to enable or disable the use of offline files for all users on the computer in Windows 7 and Windows 8.
You must be logged in as an administrator to be able to do the steps in this tutorial.

In Windows 8, offline files is only available in the Windows 8 Pro and Windows 8 Enterprise editions.
Here’s How:
1. Open the Control Panel (icons view) in Windows 7 or Windows 8, and click/tap on the Sync Center icon.
2. In the left pane, click/tap on the Manage offline files link. (see screenshot below)
3. To Enable the Use of Offline Files
NOTE: This is the default setting.A) Click/tap on the Enable offline files button. (see screenshot below)
B) If prompted by UAC, then click/tap on Yes.
C) Click/tap on OK. (see screenshot below)
D) Go to step 5.
4. To Disable the Use of Offline Files
A) Click/tap on the Disable offline files button. (see screenshot below)
B) If prompted by UAC, then click/tap on Yes.
C) Click/tap on OK. (see screenshot below)
5. Click/tap on Yes to restart the computer. (see screenshot below)
WARNING: This will restart the computer immediately. Be sure to save anything that you have open first.
6. If you enabled Offline Files, then all you need to do now is to make the network files or network folders you want to be always available offline.
That’s it,
Shawn