Clicking that popup will offer to run Windows Defender (not the successor to MSE, this is the old Windows Defender, which only offers basic anti-malware protection: difference between MSE and Windows Defender). The second callout bubble also comes from the flag icon in the tray, which is how Windows lets you know about various problems on your computer. Clicking on it brings up a security dialog that lets you re-enable MSE:

The first says ' Microsoft Security Essentials is turned off.

Second, you'll get a couple of balloon security notifications from the system tray (notification area). The main window will now display a red bar across, with the ' PC status: At risk' warning message. To (temporarily) turn off Windows Defender protection in Windows 8 / 8.1, please read ' Disable Windows Defender'.Īs soon as you do, several things will happen: first, MSE's icon will turn red, with a white ' x' in the middle: this icon is your cue that there is a problem. Note: this tutorial applies to Windows XP, Windows Vista, and Windows 7. Because this is not a recommended setting, you'll be required to enter the Windows administrator's password (unless you are running as an admin - which is not a good idea!) If you are trying to install another antivirus software, no need to go through these steps: instead, just uninstall Microsoft Security Essentials.

Since you want to catch viruses before they infect you, disabling MSE -or Windows Defender- kind of defeats the purpose of an antivirus protection! Without active protection, you won't know if you are getting infected until you scan your PC. By default, Microsoft Security Essentials runs all the time, with its 'real-time protection' turned on: it is constantly monitoring network traffic, files you download (and viewing web pages) or files otherwise added to your computer (external USB flash drive, copy-pasting through the local network, etc.) But you can turn off MSE, which still lets you scan files for viruses, but without active protection.

Open microsoft security essentials