Solved Microsoft Security Essentials Vanished

[djl47]

I noticed Monday evening that MSE was gone, poof from my system. At first I feared malware that had disabled it but I discovered an update had failed early Monday morning. When I searched for that KB number I discovered that some users are having problems with the Windows Update package.

If you use MSE, Check to see if it is still running on your system; if not, check your update history.

Fortunately the solution that worked for me was to download the MSE package from MS, reboot, and install. Before doing that I reactivated and updated Windows Defender. (What is the difference between Windows Defender and MSE?)

My error was as follows:

Microsoft Security Essentials Client Update Package - KB2544035

Installation date: ‎2011-‎08-‎01 03:01
Installation status: Failed
Error details: Code 80070643
Update type: Important
This package will update Microsoft Security Essentials client on the user's machine.

More information: (These links took me to the MSE home page.)
http://go.microsoft.com/fwlink/?LinkId=195462

Help and Support:
http://go.microsoft.com/fwlink/?LinkId=195463

 

[mach04]

It sounds strange, I have no problem with MSE, it is both running and updates the definitions smoothly.

 

[marsmimar]

Hello djl47 and welcome to Seven Forums.

Thanks for posting that information.

Windows Defender is software that helps protect your computer against pop-ups, slow performance, and security threats caused by spyware and other unwanted software by detecting and removing known spyware from your computer.

Source

Microsoft Security Essentials provides real-time protection for your home or small business PC that guards against viruses, spyware, and other malicious software.

Source

So, Defender is pretty much an anti-spyware product while MSE is a suite of anti-malware tools.