Windows Defender is a Microsoft software application that safeguards a system from malware and all virtual threats. It was an anti-spyware program built-in to fight unauthorized access and protect Windows computers from unwanted software.
Activating Windows defender real-time protection runs a virus check on all files and applications that are downloaded or opened. Eventually, it has to be updated regularly. If you stop running real-time protection, when you open or download files, it will not be scanned for threats. However, real-time protection will soon turn on automatically again to protect your device.
Windows Defender also scans email files. Malware can install itself and hide within email files. Although real-time protection offers you the best protection from email malware, you can also scan emails stored on your PC or server with Windows Defender.
If it found any threats, Windows Defender Email Protection will alert you through notification.
Now, Windows Defender Email Protection will automatically turn ON. If you're running Windows 10 for Enterprise, turn ON the Microsoft Defender Antivirus by removing all other antivirus programs from your computer.