Understand System Restore

System Restore is an XP service that runs in the background, continually monitoring changes to essential system files and the Registry. Then, if Windows becomes unstable, you can use the System Restore in either Normal Mode or Safe Mode to roll back your system files and registry settings. To perform a Safe Mode startup, hold down the F8 key as Windows starts up.

Rolling back can undo changes that may have caused system instability. In other words, the System Restore acts as a sort of time machine, transporting your installation of XP back in time to a point where it was working properly. And here's the really cool part: it does this without affecting personal data such as Word documents or email files. That is, you can roll back XP so that it behaves the way it did three months ago, yet still have all the changes you made to your book chapter yesterday.

The System Restore is especially effective in the following situations:

• You install a program that conflicts with other software drivers on your system. If uninstalling the program doesn't fix the situation, you can restore to a point before the program was installed.

• You install one or more updated drivers that cause system instability. System Restore can restore all previously installed drivers instead of using the Driver Rollback feature from Device Manager.

• Your system develops performance or stability problems for no apparent reason. This situation may not seem plausible at first glance; after all, problems always occur for a reason, right? But consider a situation in which a computer is shared by many people who may or may not document changes they make or install untested or unsupported software or devices without compatible drivers. You can restore to a point where you are reasonably sure that the system was functioning properly (that is, the last time you were using it).

Now, just because System Restore can turn back the clock, you shouldn't count on it to replace a good antivirus program. A system can become infected and not exhibit any symptoms for a while, and files identified in restore points can be infected without your knowledge. Plus, a system can become infected and then spread its malaise to other computers.

By default, System Restore creates restore points without user intervention every 24 hours if you leave your computer on. Also, if you shut down your system, System Restore checks to see when the last restore point was created. If it's been more than 24 hours since the most recent restore point, System Restore creates a new one.

There's more. At regular intervals, System Restore takes snapshots of the System State, looking at the same type of information that is saved when you back up System State data. If SR detects a major change, it createsyou guessed ita restore point. For example, if you install a program such as Microsoft Office, chances are that a restore point will be generated, as shown in Figure 13-11

Figure 13-11. Most restore points are created automatically.

Additionally, you can create a System Restore point by your own damn self if you feel one is merited. You might want to double-check after a major change or upgrade, and if one's not there, go ahead and create it.

How? Use the Help and Support Center. Choose the "Undo Changes to your computer with System Restore" task in the Task List, and then choose the "Create a restore point" radio button, as shown in Figure 13-12.

Figure 13-12. Create a manual System Restore point.