MS Security Essentials turned my lightning computer into a snail

Do you have modern hardware? Is this a fresh install of Win 7 in bootcamp?

If it is a VM i think VMs are simply slow.

I use MSE on all my Win 7 installs (a dozen within the past few months) because I think it is light on resource usage. So, if you are using modern hardware, I suggest a fresh install of the OS, and after OS updates, install MSE. I have had no experience with slowdowns (like with symantec) so if you do, then open resource monitor and tell us exactly which program is being a resource (memory/cpu) hog.

 

Ive used MSE for a year on a 1.66GHz C2D Win7 machine. My father has been using it on his 900MHz Celeron. MSE is very transparent, the only time it loads the processor noticably is when it's doing an occasional scan.

Check the Task Manager (show all processes) to see what's using resources.

 

I'm with the other folks on this one. I run it on my Win 7 machine with no problems. Yeah, it's got a good proc and a ton of RAM, but it is still barely noticeable. I also installed it on my mom's older WinXP PC and it didn't impact performance at all. In fact, I found it a bit less intrusive than the AVG free I had on it before.

 

Yes i also use Microsoft Security Essentials. it gives you excellent performance and powerful security.and the great thing is its free to download and update.