Microsoft Security Essentials problem.


Excellent Member
Microsoft Community Contributor
I am currently trying to determine if MSE is having a problem that Microsoft is not addressing.

If you check the Event Viewer and show a SxS error or a Microsoft Anti-malware error, it might be caused by a problem with MseSysPrep.DLL.

It seems running the Scheduled Task related to Application Experience will show a problem with MSESysPrep.dll. Many folks are showing the error and I am having a problem with the MSE real time protection shutting down because of "updates".

I do not feel shutting down the real time protection for MSE updates is appropriate, so I will be watching to see if Microsoft addresses the problem.

Anyone see anything related to the problem?


Essential Member
Premium Supporter
Hi Saltgrass. Sorry, fwiw. I have my updates as "Check for updates but...." etc., This includes MSE updates. I automatically say yes to them and have never experienced your error.
But, after reading your post, I browsed a little and I see that the suggested cause of this is running more than one security service and causing a confliction??
Also, one remedy appears to be running your cleaner (Ccleaner preferred) in safe mode.


Excellent Member
Microsoft Community Contributor
This is not really an Update problem, or at least I don't think it is.. When the ProgramDataUpdater Task runs the Side by Side error is generated.

Activation context generation failed for "c:\program files\microsoft security client\MSESysprep.dll".Error in manifest or policy file "c:\program files\microsoft security client\MSESysprep.dll" on line 10. The element imaging appears as a child of element urn:schemas-microsoft-com:asm.v1^assembly which is not supported by this version of Windows.
The task is in Task Scheduler, under Library, Microsoft, Windows, Application Experience. I have not yet determined if this error is related to the Real Time protection shutting down, but still investigating. The Real Time error might just be a temporary situation that corrects itself. I just see the errors in the Event Viewer.

This has been going on for quite a while, so there is probably no hurry in solving it. Just trying to understand what is causing it. I am only running MSE.


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