Viruses and malware can cause many problems on a computer. If you suspect your computer has a virus or malware infection, review the sections below for help and suggestions on quarantining or eliminating the infection.

Virus detection and removal

If your computer or storage device, like a USB flash drive, is infected with a virus or malware, run an antivirus scan on the computer. Open your antivirus scanner through the Windows notification area or Start menu and run a full system scan to check all files on your computer for a virus.

If you’re concerned about a specific file being a virus, see: Is this file infected with spyware, virus, or other malware?

If you’re unable to boot to Windows, boot the computer to Safe Mode and run the scan from Safe Mode.

By default, antivirus programs usually scan the primary hard drive on a computer and not other storage drives, like USB flash drives. Access the settings in your antivirus program and make sure it is set to scan all drives connected to the computer.

  • How to open Safe Mode.

Removing detected virus

If the antivirus program detects the virus, a prompt to move the virus to the virus vault or delete the infected files are given. Both options are a good way to remove the virus from the computer.

I don’t have an antivirus program installed

Try running an online virus scan if you do not have an antivirus or Windows Defender but still believe a file is infected with a virus. These websites scan your computer hard drive for any infections.

If you are running Windows 8, Windows 10, or Windows 11 on the computer, you may be using Windows Defender as your antivirus.

  • Where can I find free online virus scanners?
  • What are the currently available antivirus programs?

No virus is detected

Unfortunately, many non-virus-related issues are often blamed on computer viruses. Nine times out of ten, a computer problem is a software, driver, or hardware-related issue and not a virus. If no viruses are found after running the antivirus scan, it’s very likely the computer is not infected. If you still believe your computer is somehow infected, you may also consider running an online virus scan and scanning the computer with a malware protection program, as mentioned below.

We don’t recommend manually finding and deleting files on your computer if you suspect you have a virus. Deleting the wrong files could result in errors on your computer or cause the operating system to become unusable.

  • Where can I find free online virus scanners?

Malware, spyware, and adware detection and removal

Some antivirus programs, like Webroot SecureAnywhere, include malware protection in addition to virus protection. If your antivirus program does not include malware protection, we strongly recommend running a malware protection program, such as Malwarebytes. Malware can cause computer errors and other problems.

How to scan the computer or get software if the Internet is not working

If your Internet is not working, follow the steps below to get a protection program on your computer.

  • Download antivirus software, such as Malwarebytes, to another computer. Then, transfer it to a USB thumb drive, and use the thumb drive to run Malwarebytes on the infected computer.

  • Copy the download to a USB flash drive.

  • Install the program from the flash drive on your computer.

  • How to install software.

  • How does a computer get infected with a virus or spyware?
  • How to scan or check for computer viruses.
  • What are the currently available antivirus programs?
  • If I format or erase my hard drive, will it remove a virus?
  • See our malware and virus definitions for further information.
  • Computer virus help and support.