Verifying the Repair

A repair is not complete until you make sure the computer is functioning correctly. Sometimes you may fix one problem only to find another.

These are the criteria to use to determine if a problem has been fixed:

• The entire problem has been resolved.

• No new problems have been introduced during the troubleshooting and repair.

• All elements of the system work correctly together.

To verify the repair, try to recreate the problem:

• Restart the computer. See if the problem recurs.

• Open all affected applications and files.

• Run MacTest Pro, Apple Hardware Test, or Apple Service Diagnostic (if available) to test the entire system, even if only one part of the system was repaired. If possible, run looping tests for several hours, to catch any intermittent problems. Use Verify Disk and Verify Disk Permissions in the First Aid pane of Disk Utility. Use Network Utility to test networking.

• Run System Profiler to review the before and after state of connected devices. This ensures that you did not fix one problem device and introduce another.

• Review logs in Console. Use the filter in Console to check for error messages.

• After you have finished validating the fix, print reports for your end user, if possible. User notification is important to help with the human factor: If the person using the computer is not convinced that the repair was successful, he or she might be more likely to report "phantom problems" (normal computer behavior that the end user interprets as a problem, or minor transient issues).

Problem ScenarioVerify Repair

You've solved a problem with erratic performance by the invasive quick fix of an Archive and Install of Mac OS X.

When the installation completes, you verify the repair by having the customer open some applications she uses often. Double-clicking some of them causes them to appear briefly, then disappear. Also, some other applications are behaving erratically.

Because you archived and reinstalled the system, this suggests that a possible explanation is an application/framework mismatch. Application/framework mismatches are often caused by performing an Archive and Install without performing Software Update afterward.

An Archive and Install archives the operating system (including frameworks) and bundled applications. However, newer applications than the version being installed are not archived. So, you may have, for example, a newer version of Safari than the WebKit framework installed from your Mac OS X Install DVD. Using Software Update and updating to the current version of the operating system should resolve this.

To solve the problem completely, you need to make sure the customer completes the necessary software updates.