Antivirus software can become vulnerable when it is not regularly updated. A key element in antivirus design is matching a possible virus threat against those contained in a library of known pests. In essence, the antivirus program checks for known suspects and if there is a match to one described in the library, the antivirus program identifies the culprit and takes steps to eliminate its impact. In antivirus jargon, this is this is know as a the signature library (or signature file). If your signature file is not up to date, then it is possible that new viruses can slip through since the antivirus software is not aware of the new pests’ existence. From time-to-time, updates are also released for the antivirus program itself that help make it more effective and reliable.Like other antivirus software, Microsoft Security Essentials (download a copy here) is designed to automatically update from the internet on a regular basis without you having to do go through the whole process of checking every few hurs for an update and downloading it manually. In most cases, this is the best way to keep up to date and secure. The problem is that some computers may not have stable or regular internet connections to download files that can range from as little as 1MB to over 50MB. At other times, internet connections in some parts of the world may have strict download limits or speeds. In addition, you may want to update a computer that is not connected to the internet or have several computers and not want to wait for the same signature files to be downloaded individually on each system. The solution is to manually download the latest Microsoft Security Essentials signature file and then update one or more PCs with that release.
- Note: This is a permanent link that will download the latest signature updates from Microsoft's servers. Updates can be released several times a day and this link will automatically download the latest official Microsoft release.
- The file can also be used to update Microsoft Forefront
- To check the version number of a downloaded signature file, right click on the signature file and choose Properties from the menu (it's at the bottom). Click on the Version tab. At the top will be the heading 'File Version' with a string of numbers next to it, such as 18.104.22.168. To check the currently installed signature file, open Microsoft Security Essentials and click on the update tab at the top. Compare this number on this page to the signature file and decide if you need to run the update. If you want to see which version you are downloading, see the next point.
- The Window shown below is live from the Microsoft site and displays the version number and release date of the file you are about to download.
DOWNLOAD Microsoft Security Essentials and Microsoft Forefront Definitions update