There are times when you have to reset the Windows system on your computer, for example because of a virus attack, a corrupt update file, or a computer that is currently running slowly or doesn't open properly. There are several ways that you can try to normalize your computer system. Follow the guide below for tips.
Step
Method 1 of 4: Boot in Safe Mode to Fight Virus
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Step 1. Use Safe Mode
Safe Mode is the best mode to start repairing a damaged computer. This mode can be used to combat several types of viruses, as well as serve as a diagnostic tool if you are in doubt about the cause of a malfunctioning computer. If your computer starts and functions in Safe Mode, the problem is with another program, drive (driver) or file, not the computer.
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Step 2. Restart the computer in Safe Mode
Select Safe Mode from the Shutdown menu, if it is accessible.
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Step 3. Press F8
If the Shutdown menu is inaccessible, you can restart your computer and press F8 continuously while it will load Windows. This method is to give you access to the Boot Menu.
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Step 4. Select Safe Mode and press Enter
Press the down arrow key to access the Safe Mode options and press Enter.
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Step 5. Start repairing the computer
Once you've logged into Windows, you can start repairing your computer. There are a number of ways that you can try and use, but each one depends on the type of problem at hand.
- Delete all files associated with system-recognized viruses, which usually make them inaccessible.
- Download or run an antivirus program that is normally inaccessible due to a virus. You may have to restart the computer in Safe Mode with Networking mode.
- Uninstall any recently installed programs that you suspect are the source of the problem.
- Update all drivers if you suspect that an outdated driver is the problem.
- Run System Restore, which is similar to Last Known Good Configuration below. Do this by searching for System Restore from the Start menu and following the prompts. Don't forget to scan all affected programs.
Method 2 of 4: Configuration Changes to Fix Driver Problems
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Step 1. Use Last Known Good Configuration mode
This method is suitable if you believe the problem is caused by a bad driver or system update. This method can also fight some types of viruses.
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Step 2. Remove any storage media from the computer
Remove all CDs, DVDs, USBs and floppy disks from the computer.
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Step 3. Restart the computer
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Step 4. Press and hold the F8 key while the computer starts up
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Step 5. Press the down arrow key to select Last Known Good Configuration
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Step 6. Press Enter
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Step 7. Allow the computer to restart
It may take a minute or two longer than usual, as the system is recovering itself. Finished!
Method 3 of 4: Wiping the Computer with the Installation Disc
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Step 2. Take the installation disc
Get a Windows 7 installation disc. Your PC probably has one. If you don't have one, buy this disc from your nearest computer store.
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Step 3. Open the disc tray (disk tray)
Open the PC disc tray, then turn off the PC while the disc tray is open. The computer will now shut down and the disc tray will remain open.
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Step 4. Insert the Windows 7 installation disc
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Step 5. Turn on the computer
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Step 6. Press any button to start
Immediately the message Press Any Key to Boot from CD will appear. Press any key to continue.
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Step 7. Follow the simple instructions that appear on the screen
Method 4 of 4: Wiping Computer Contents as a Last Effort
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Step 1. Back up all your data
If possible, back up your data before wiping the contents of your computer, as all your data will be erased.
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Step 2. Prepare a replacement OS
You will need a Windows 7 installation disc or an alternative OS (operating system) (eg Linux which is free), because the OS on your computer will also be deleted and you will need a new one if you want to use the computer again.
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Step 3. Download Darik's Boot and Nuke (DBAN)
You must download a program to safely wipe the computer. DBAN is a common program for that, just like Active@KillDisk. Make sure you download this program from a trusted source.
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Step 4. Insert this program on CD or USB device
This program must be included in the type of storage device that the computer can load.
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Step 5. Shut down the computer
Step 6. Insert the disc or USB device that contains this program
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Step 7. Turn on the computer from the disc or USB
The process will run automatically. If not, you will need to enable it from BIOS settings. Turn on the computer and when it will load press the F10 or F12 key (depending on your system and keyboard) to access the Boot menu. From there you can specify the first boot whether to be from a USB or a CD. Turn off the computer. After the computer restarts, it will run the specified device.
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Step 8. Type "dodshort"
Once the computer boots up from the disc, the quickest way to erase the computer is to type "dodshort". You can also unlock interactive mode for more options.
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Step 9. Press Enter
Press Enter and the computer will start wiping.
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Step 10. Reinstall the operating system
Once the contents of the computer have been erased, reinstall the operating system and the computer will once again work. You can simply restore all existing backup files.