Reverse Damages and Mistakes
Everyone makes mistakes... and
Microsoft (and other software makers) know that. No matter if you've made a bad
change in the registry or emptied the Recycle Bin after deleting your only copy
of a report due the next day, there are ways to "undo" the damage.
- Use Last Known Good Configuration to Back
Out of a Recent Change
- Go Back in Time With System Restore
- Restore Important Files With System File
Checker
- Undelete Files With a File Recovery Program
How Do I Start Windows Using Last Known Good Configuration?
Question: How Do I Start Windows Using Last Known Good Configuration?
Starting Windows using Last Known
Good Configuration (LKGC) is very often the best first step when
troubleshooting a Windows startup problem.
As the name implies, starting Windows
using Last Known Good Configuration starts Windows using the registry and driver
configuration that worked the last time Windows was started and shut down
properly.
Since drivers and registry issues
are common reasons why Windows won't start, Last Known Good Configuration can
be a very valuable tool in troubleshooting Windows startup issues.
Answer: You can start Windows using Last Known Good Configuration
from the Advanced Boot Options menu.
Starting Windows using Last Known
Good Configuration is pretty simple but the exact method differs a little
depending on which Windows operating system
you're using:
Note: In most cases, if your Windows startup problem is not
solved by starting with Last Known Good Configuration, the next step would be
to attempt a System Restore. However, if
you came here from a specific troubleshooting guide, your best bet is to follow
whatever troubleshooting step is listed next.
Important: The changes made when starting Windows using Last Known
Good Configuration can not be undone. Don't let this deter you from trying Last
Known Good Configuration - a working Windows with the previous session's driver
and registry data is much better than Windows that you can't access at all.
How Do I Use the Windows System Restore Utility?
Question: How Do I Use the Windows System Restore Utility?
The Windows System Restore utility is one of the most
valuable recovery tools available to a Windows user.
Many of the more serious problems in
Windows are caused by device driver
issues, missing or corrupt DLL files,
and problems with the Windows Registry -
all parts of Windows that a System Restore can help with.
The System Restore tool is one of
the easiest to use recovery utilities available in Windows.
Answer: The Windows System Restore utility is located in the System
Tools program folder and provides a step-by-step process for restoring
important Windows files.
The System Restore tool in Windows
works fairly similarly among Microsoft's operating
systems but there are some important differences:
How To Use SFC /Scannow to Repair Protected Windows Operating System Files
Sfc /scannow will inspect all of the important Windows files on your computer, including Windows DLL files. If System File Checker finds an issue with any of these protected files, it will replace it.
Important: You can only run the sfc /scannow command from an elevated Command Prompt. See How To Open an Elevated Command Prompt if you need help doing that.
Follow these steps for using sfc with the scannow option to repair important Windows files:
Difficulty: Easy
Time Required: Using sfc /scannow to repair important
Windows files usually takes 5 to 10 minutes.
Here's How:
1. Open
Command Prompt.
Important: You must run Command Prompt as an
administrator in Windows 8, Windows 7 and Windows
Vista to use System File Checker.
2. Once
Command Prompt is open, type the following command and then press Enter.
3. sfc /scannow
Note: There's a space between sfc and
/scannow.
Important: If you're trying to use System
File Checker from the Command Prompt available in System Recovery Options,
see Tip #1 at the bottom of the page for some changes in how you execute sfc
/scannow.
4. System
File Checker will now verify the integrity of every protected operating
system file on your computer.
Note: In some situations, especially in Windows
XP and Windows 2000, you may also need access to your original Windows
installation CD or DVD.
5. Restart
your computer if sfc /scannow did actually repair any files.
Note: System File Checker may or may not
prompt you to restart but even if it doesn't, you should restart anyway.
6. Repeat
whatever process caused your original problem to see if sfc /scannow corrected
the issue.
Tips:
1. When
running sfc /scannow from outside of Windows, like from the Command Prompt
available when you boot from your Windows disc or flash drive, or
from your system repair disc, you'll have to tell the sfc command exactly where
Windows exists, as in this example:
2. sfc /scannow /offbootdir=d:\ /offwindir=d:\windows
The /offbootdir= option specifies the drive
letter, while the /offwindir= option specifies the Windows path, again
including the drive letter.
Note: Depending on how your computer is
setup, the Command Prompt, when used from outside of Windows, doesn't
always assign drive letters in the same way that you see them from inside
Windows. In other words, Windows might be at C:\Windows when you're using it,
but D:\Windows from the Command Prompt in System Recovery Options.
In most installations of Windows 8 and Windows 7,
C: usually becomes D: and in Windows Vista, C: is usually still C:. To check
for sure, look for the drive with the Users folder on it - that will be
the drive Windows is installed on, unless you have multiple installations of
Windows on multiple drives.
