Microsoft Security Essentials

Microsoft Security Essentials is recommended for those who want something to set and ignore, but users who want more robust configuration choices or don't want to contribute to the cloud should look elsewhere.

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Microsoft has released version 1.0 of Security Essentials, the successor to Live OneCare. Originally known as Morro, Security Essentials retains the core features of OneCare, but abandons the additional heft of a firewall, performance tuning, and backup and restore options in exchange for making the program free. Rather than taking aim at full-featured security suites made by Symantec or Trend Micro, the features available in Security Essentials indicate that Microsoft is aiming to compete with basic-but-free security apps.

For the select 75,000 public beta testers who got their hands on the program when the limited public beta was offered in June, there will be few appreciable differences between the beta and the final version. For the rest of the planet, Security Essentials features key defences that are boilerplate for any respectable security program.


It uses both definition file and real-time defences against viruses and spyware, and also offers rootkit protection. The program's reputation-based detection and software signature-based detection seem to rely heavily on Microsoft SpyNet, the unfortunately named cloud-based service that compares file behaviour across computers running various Microsoft operating systems.

SpyNet was introduced in Windows Vista and extended to Windows 7, but Microsoft Security Essentials is the only way to access the network on Windows XP. Unlike other security vendors that allow customers to take advantage of the benefits of their behavioural detection engines while opting out of submitting information, there's no way to do that with SpyNet.

You can choose between two SpyNet memberships. Basic submits to Microsoft the detected software's origins, your response to it and whether that action was successful, while the Advanced membership submits all that plus the location on your hard drive of the software in question, how it operates, and how it has impacted your computer. Both basic and advanced warn users that personal data might be "accidentally" sent to Microsoft, although they promise to neither identify nor contact you. Opting out of SpyNet, however, is not an option in Security Essentials.

Security Essentials benefits greatly from having a simple, streamlined interface. There are four tabs, each with a concise and understandable label: Home, Update, History and Settings. The program also uses easy-to-grasp labels, imported from OneCare: green for all good, yellow for warning, and red for an at-risk situation.

From the Home window, you can run a Quick Scan, Full Scan or Custom Scan, and a link at the bottom of the pane lets you change the scheduled scan. The Custom Scan lets users select specific folders or drives to scan, but it doesn't allow for customising the type of scan used. For example, you're not going to be able to choose to scan only for rootkits or heuristics, as you can with other security programs. The program installs a context-menu option for on-the-fly scanning in Windows Explorer, too.

The Update pane manages the definition file updates, with a large action button, and History provides access to a spreadsheet-style list of All detection items, your Quarantine, and items you've Allowed to run. Although it's a basic layout, this no-frills approach to security could prove appealing to computer users who are overwhelmed by more detailed security choices.

The Settings window allows users to further customise the program by scheduling scans, toggling default actions to take against threats, adjusting real-time protection settings, creating whitelists of excluded files, file types and processes, and the aforementioned SpyNet options. There's also an Advanced option which is still fairly basic: here you can set Security Essentials to scan archives, removable drives, create a system restore point or allow all users to view the History tab.

Security Essentials comes pre-configured to run a scan weekly at two in the morning, when your Microsoft thinks your system is likely to be idle. New malware signatures are downloaded once per day by default, although you can manually instigate a definition file update through the update tab. Attachments and downloaded files will be automatically scanned by Security Essentials.

Help is only available in the form of the standard offline Help manual that comes with all Microsoft programs. There's nothing fancy here.


It installed in less than one minute and completed its first Quick Scan in less than 30 seconds. The Full Scan took more than an hour to reach the halfway point, and this was borne out by tests performed by CNET Labs' benchmarks. Microsoft Security Essentials actually sped up the boot time of our test computer by more than two seconds, and it sped up the shut-down time by more than two and a half seconds. However, compared to major security vendors it was significantly slower at scanning — Security Essentials took 2340 seconds to scan, whereas most scans would clock in between 1000 and 1100 seconds.

In our iTunes decoding test it scored similarly to its competition, about seven seconds slower than an unsecured computer. In our MS Office test and media multitasking tests it was faster than some — 503 seconds versus 552 seconds for Norton AntiVirus 2010 in the Office test, and 844 seconds versus 876 seconds for Trend Micro Internet Security Pro in the media test.

Running the Full Scan took up about 86MB of RAM. However, it felt far lighter, and we were able to perform resource-intensive tasks like uploading photos without any noticeable freezes.

Third-party virus detection efficacy scores were not available at the time of writing, and it's not currently clear whether Security Essentials shares the same detection engine as Live OneCare. However, CNET reporter Ina Fried mentioned that Security Essentials stopped her from accidentally coming down with a case of Koobface.


Microsoft Security Essentials is a lightweight security app that people might turn to for a number of key reasons. It's easy on the system resources, it's easy to figure out how to use, and it comes pre-configured. It only works on legally licensed Microsoft computers, which is understandable but potentially leaves a large segment of the unprotected population still unprotected. You can't opt out of contributing to SpyNet, which isn't understandable at all. Overall, it's recommended for those who want something to set and ignore, but users who want more robust configuration choices or don't want to contribute to the cloud should look elsewhere.

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TerryA posted a comment   

joined the prerelease program...should be interesting....

Navy seal, Jh

Navy seal, Jh posted a review   

The Good:Its light on cpu and resources!

The Bad:... :I

Not a problem at all :I


DimitriAus posted a comment   

The Good:fast, free

The Bad:Does not scan e-mails !? Does not scan web pages!?

I do not see any settings for e-mail or web antivirus. Does MS antivirus actually scan incoming e-mails and browsed WebPages?


davedo posted a review   

I run MSE and no problems are detected. I then run Spybot and there is always a potential threat though relatively small usually. MSE updates and it always upsets my setting and an upgrade leaves me entirely without my desired search option(Google).Everything works slower with it but then it is supposedly filtering along with the firewall and spybot Don't ask if it works because I have no Idea. But as a pain in the **** it is King.


dep posted a comment   

The Good:it increase my laptop speed

The Bad:scan takes time than bit defender

before i used bit defender for more than ten months suddenly i found this Av yesterday after installation my laptop speed up start and shut down


thinkingmatter posted a review   

The Good:?

The Bad:?

I'm not quite how to rate this free antivirus/spyware application. I have had it running on 2 laptops since OneCare ceased (several months). Very easy to use; slow full scan; however, not one instance of virus, malware or spyware has been detected during all those months on iether laptop. Makes me wonder: is it capable of serious detection?


rahjed posted a comment   

The Good:Very Light, Seemless and Easy To Use

The Bad:Watch Out For Fake MSE Pop Up Messages

My system was wiped out by this AV, did not realise the fake AV via an email that looked genuinely from MS, wiping my computer and locking EVERYTHING - INCLUDING my expension USB backup drive wilst MSE was running.

MS need to upgrade this AV, even if it becomes a "Pay For It" - in essence a light and really easyily used AV.

See Rob Above - 11/11/10 - "A Toy", this is the reality of MSE! TAKE CARE!


StrikeyMate posted a review   

The Good:Light on CPU

The Bad:Slow scanning

There's a lot to like about MSE and only a little not to like, but hey, it's early days guys. As far as I can see there is not much to improve on, so with later releases looming I see a big future for this product. Don't know how it did it, but MSE seems to have improved my start-up and shutdown times. Never ever thought I would say this...but well done MS and keep it going.


MSElo♥er posted a review   

The Good:VERY reliable!!!!!!!!!! BRAVO Microsoft ♥♥♥♥♥♥♥

The Bad:PLEASE Improve its speed a bit and it's unbeatable!

NOD32 is a brilliant AV. I have used ESET Nod32 on my PC for many years and I was never infected. But lately, I switched to MSE. It's much lighter than NOD and also exceptionally good.

Giz of Oz

Giz of Oz posted a review   

The Good:Works Nicely With My Laptop

The Bad:Time For A Newer Version

Well I got adventuresome and tried out some of the other freebies,(and guess what?), I'm back to using Microsoft Security Essentials on my laptop. Why? Because it's the only a/v that doesn't slow down the computer. The other freebies had a significant "hog-attack" on my cpu and memory, and all had a dramatic impact on my start-up time. I use MSE in conjunction with Zone Alarm Free and, to date, no infections. For added protection still using WOT, Malwarebytes, and Microsoft's Malicious Removal Tool. Also thrown in Spybot Search and Destroy and Virus Total Uploader to add to my collection of free tools. The search is over...

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User Reviews / Comments  Microsoft Security Essentials

  • TerryA


    "joined the prerelease program...should be interesting...."

  • Navy seal, Jh

    Navy seal, Jh


    "Not a problem at all :I"

  • DimitriAus


    "I do not see any settings for e-mail or web antivirus. Does MS antivirus actually scan incoming e-mails and browsed WebPages?"

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