Explanation/Reference:
Explanation:
Chapter 1 Lesson 1 p 17
Appendix C p 485 / 486
Chapter 5 p 275 / 276

How to Roll Back to the Previous Version of a Device Driver:
Device Driver Roll Back reinstalls the driver you were using previously and restores any driver settings that were changed when you added the new driver. To roll back a device driver to a previous version:
Log on to the computer by using an account with administrative privileges.
Click Start, and then click Control Panel.
Under Pick a category, click Performance and Maintenance.
Under or pick a Control Panel icon, click System.
On the Hardware tab, click Device Manager.
In the device list, expand the device type branch that you want to work with. For example, Display adapters.
Right-click the device that you want to work with, and then click Properties.
On the Driver tab, click Roll Back Driver. Click Yes when you receive the following message:
Are you sure you would like to roll back to the previous driver?
The previous device driver is restored. Click Close.
10. Quit Device Manager, and then click OK.
Note: that you cannot restore printer drivers with Device Driver Roll Back.
Driver Roll Back only allows you to roll back a driver once. In other words, Windows 7 only keeps a copy of the very last driver installed. It does not keep an archive of all previously installed drivers for the device.
http://pcsupport.about.com/od/windows7/ht/roll-back-driver-windows-7.htm