Microsoft Security Essentials is an anti-virus, anti-spyware and anti-malware developed by Microsoft that is available free for home users and small businesses.

Having a basic protection in Windows operating systems is essential to be able to make use of PC. If we don't have an antivirus or antispyware, in a very short time, our PC will be affected by some kind of malware or virus that exists on the Internet.

Microsoft Security Essentials is presented as an effective solution to viruses, trojans, adware, spyware, and other malware. If we have installed the operating system, and your PC doesn't have any anti-virus, this software will be perfect for us because it's free and offers a basic protection for Windows XP, Windows Vista and Windows 7. Can be used free for home users and small business (up to 10 computers).

Software's installation is quick and easy. Once installed we will see a small icon on the right side of taskbar. This icon indicates the status of the computer protection, if it is green it means that PC is protected against threats.

To open the program, we can double-click on the icon in the task bar. Once opened, it displays a screen where we can see a summary of the status of protection. It will show when was the last virus scan, and when is scheduled the next scan. We can also run a scan: quick, full or custom.

The release of new viruses and variants of old ones, make it necessary to have an antivirus with the latest virus information, and also can be upgraded easily. In this case, this antivirus program automatically updates virus, malware and other threats database, without our intervention. So we always will have fresh protection against viruses. At any time we will have the option of clicking on the “Update” button to force the program to download the latest virus and spywares definitions.

If the anti-virus detects a malicious software, it warn us, and assign a level of alert to detected threat. Alert levels are:

• Maximum: potentially dangerous threat. The anti-virus will attempt to eliminate the threat without prompting the user.
• High: a threat that can affect user 's privacy and damage the system. Anti-virus will attempt to delete the threat, without consulting the user.
• Medium: threat that can have a negative effect on the computer and user's privacy. The antivirus asks what we want to do with that threat.
• Low: threat that can collect information about the computer and make changes on it. The antivirus will ask us what action we want to perform against the threat.

When the anti-virus detects a threat, it shows us several things we can do:

• Delete: the anti-virus will attempt to delete the detected threat, deleting all the files that are infected.
• Quarantine: this option allows us to disable the file containing the threat. To do this, the antivirus moves the infected file and it will be located in a place where it can't run automatically. Once we decide what we will do with that file, we can remove it from the quarantine, to either delete it, or to guarantee access to our system.
• Enable: if we trust the file that is triggering the alert, we can allow it to run. We should use this option with caution because we run the risk of giving access to malicious files.

At any time we can see the history of threats found, deleted, quarantined, and allowed. In this way we can see when was the first time that a virus was detected, or when a certain threat was removed.

Despite the fact that Microsoft Security Essentials is a basic antivirus, it has advanced options that will be enough for a lot of users. Some of these options are:

• Schedule scan: we can choose the day of the week and time when the scan starts. We can limit CPU usage while auto scan, and avoid overloading the PC and slow down the rest of ongoing operations.
• Real-time protection: this option allows the antivirus to scan all those programs and files that try to be installed or saved on the computer. In this way we'll solve the problem before it happens, since the antivirus will detect the threat and act accordingly to the danger associated with such a threat.
• Examine compressed files: this option enables the analysis of the files inside .zip, .rar, .cab, etc.
• Create a restore point: if we mark this option, it will create a restore point just before we delete or quarantine detected threats.
• Delete quarantine files: this option allows us to define the expiration time for files in the quarantine folder. We can choose between 1 day and 3 months. If for example we chose 3 months, all those files that have been in quarantine for 3 months, will be deleted from the computer. This way we avoid the store unusable and infected files in our system.

There are most powerful antivirus that this one, but if we still don't know which antivirus to purchase, this will be a perfect solution to be installed while we decided to go for a most complete antivirus program.