Microsoft bundles Windows Defender as the default antivirus in Windows 10 to provide basic security against common threats like virus, spyware, trojan and other malware. Since, Windows Defender is deeply integrated with the operating system, the virus definition updates are delivered via Windows Update. So, if you have made changes to Windows Update settings it is possible Windows Defender is not getting automatic updates regularly. You will learn how to manually update Windows Defender if your PC is online and you have disabled Windows Update. If your PC is offline, you will learn how to get Windows Defender offline update in Windows 10.
Microsoft has released Windows Defender Offline, an offline antivirus tool, for PCs that are badly infected by malicious and other potentially unwanted software, including rootkits, to even get full access to the Internet.
The offline antivirus tool basically allows a user to boot their infected Windows computer system from a CD, DVD or USB flash drive. It uses the most recent definition update available to scan the PC for malicious and other potentially unwanted software. It then helps the user to disinfect the PC from the hard to detect threats.
This tool is particularly useful to remove certain kinds of malware that prevents the user from visiting any security or antivirus website. Many malicious programs uses methods to prevent users from accessing those websites to prevent detection and cleaning. Sometimes, they corrupt Windows files to prevent any kind of network access.