How to quickly find and delete viruses in your computer with Windows 8

First, scan your computer with Windows Defender
Open "Windows Defender" by swiping from the right edge of the screen to the middle, click "Search" (If you use the mouse, point to the top right corner of the screen , then move the pointer down, click "search"), enter Defender in the search box, and then click or click "App" and "Windows Defender".
In "Scan Under Options ", select the type of scan you want to run:
"Fast" Scan only checks the areas of the computer that are most likely to be infected with malware, and all applications that are currently running.
"Complete" Scan will check all files on your hard drive. This scan can take an hour or more depending on your computer.
"Custom "Scan only checks the selected file and location.
Click or click "Scan Now".
Second, Manually Remove Viruses
Sometimes you must manually remove the virus. This process is technical in nature and can only be tried if you are familiar with the Windows registry and know how to view and delete system files and program files in Windows.
First, run an anti-malware application to identify viruses by name. If you don't have an anti-malware app, or if the anti-malware app doesn't detect a virus, you can still determine if it's a virus by looking for clues about how it behaves.
Make a note of the text in all messages displayed by the anti-malware application, or if you received the virus via email, write the subject line of the message or the name of the file attached to the message. Then search the anti-virus provider's website for reference material on what you've recorded, and try to find a description of the name of the virus and how it was removed.
Recovery and Prevention
After you remove the virus, you may need to reinstall some software or restore the missing information. Regular backups of files can help you avoid losing data when your computer is infected again. If you have not done a backup in the past, it is recommended that you do so from now on.