Thanks for the response. In the meantime, I rebooted. Surprise! mbamservice.exe as well as the folder and files in "Program Files". Of course, I should have tried that in the first place. Someone once told me, about computers, that rebooting should be the first step in trying to solve a problem. True in this case. As for the Microsoft Security Essentials tech, after messing around a long time, he did solve the problem I was having. MSE had been running at 85%-100% of CPU with System Mechanic installed, even when no application was open. Now it's down to 2%-5%.and the system has speeded up a lot.