MsMpEng.exe (Microsoft Security Essentials) has suddenly / recently been using a lot of CPU time, to the point that performance is lagging (Win 7 Pro+SP1), especially for IE11.
If I open MSE control panel and turn off real time protection, CPU usage drops. I can turn real time protection back on as soon as CPU usage drops, and things are ok for a while...
Don't have any MSE scans scheduled so only real time scanning is active.
I've seen posts suggesting to add C:\Program Files\Microsoft Security Client\MsMpEng.exe to the list of excluded files and locations as the fix for this. I would think this should only have any effect during an actual scan, but not during "real time protection".
SAS and MSE don't find any malware so I don't believe that's the problem. And MSE is fully up to date.
Thoughts and Ideas?