If you use the free Microsoft Security Essentials antivirus program, there’s an update waiting for you. The latest and greatest is version 2.0, which adds two key benefits:
- Better protection against network-based threats, scanning network traffic for signs of vulnerability.
- Better performance, thanks to an update to the core antimalware engine.
According to Microsoft, there are also fit-and-finish improvements and better integration with the Windows Firewall.
I’ve been running the beta of MSE 2.0 since July with excellent results. This is a highly recommended download.
Note that as of today this update is not available as an automatic update. Instead, you need to visit the Microsoft Download Center and kick off the installer manually:
Your Windows installation must pass validation as "genuine," and there are separate installers for 32-bit and 64-bit Windows versions.
If you run into any issues or have any questions, post a comment here.
Ed Bott 
Hey Ed, is this the the final/official version? I have been running the beta, too, but it hasn’t indicated it was a beta in the ‘about’ section since I started running it.
Seems like they would say so if it is, and wonder why it wasn’t automatic? I have gotten at least one automatic update of the beta since I started running it.
Whatever, Merry Christmas to you and the Missus !!!!!
Yes, this is the final, approved edition. I was running the beta as well but it had no beta labels on it.
MSE is what I’ve been recommending to clients as I work with them. I have had great success with it and with the clients liking it.
Thanks for the update Ed!
I setup five friends’ PCs this year with Windows 7. On four of them, I had to remove MSE because the software was using the CPU way too much and at a very high percentage, from 45 to 80 percent (more specifically MsMpEng.exe). As I have researched, this is a known bug, so regretably I now have to use more bloated AVG. It would be great if MSE 2.0 resolved this performance-impacting issue.
This is a very welcome upgrade to an already very good program. I have installed this software on many clients computers as well as my own with mostly positive results. Keep up the good work Microsoft.
@Dorian: I had the same problem on one of my Win7 laptops, although I was running MS ForeFront AV. I uninstalled ForeFront and installed this v2 yesterday and it’s not hogging the resources.
@Ed: You should mention that this update does require a machine reboot which is different than V1 which would install without a reboot.
I found this upgrade very confusing. Confusing in that there is no indication on the web site or within the program (other than “Help”, “About”) that this is version 2. I went to the web site multiple times, and not seeing a change I didn’t think there was anything different to download.
Anyway, I figured it out and installed the new version. The old one was already quite fast and very good at detecting viruses. This is a surprising, but welcome upgrade. I’ve used version 1 of MSE for as long as it’s been avialable and never had one issue. I put it on every computer I touch.
@Scott: True. Very confusing. But on the local msn-page over here ( Belgium) there is a Free antivirus option which gives you the new version. No sign however it is the new version. The new version has a CPU usage option which defaults at 50%. Good for single core cpu’s.