Scareware, also known as "rogue security software," is software that uses false error messages to lure you into purchasing a software program. These alerts or warnings may appear on websites or within applications installed on your computer. When you click the associated download link, the software is downloaded to your computer.

A typical scareware warning message will state that your computer is infected with a virus or malware without actually scanning your computer. The message will also recommend that you download software to "fix" the non-existent problem. Once you download the software, the installer may install spyware, adware, or other unwanted programs on your computer. In some cases, scareware will ask you to enter personal information, similar to a phishing scam.

In order to avoid scareware schemes, it is helpful to check the source of security alerts that pop up on your computer. If the source is not known or credible, the warning message may not be legitimate. For example, if a website advertisement says your computer is infected, you can assume the message is false, since the website has no way of actually scanning the files on your computer. Installing a utility like Microsoft Security Essentials or a third-party Internet security program may also help you catch rogue security software before it can affect your computer.

While some alerts and error messages may be scareware schemes, it is important to remember that other notifications may be legitimate. For example, the alerts provided Symantec, Kaspersky, AVG and other security programs are valid and should be taken seriously. By familiarizing yourself with the security software installed on your computer, you'll be able to determine which warnings are valid and which may be from scareware programs.

Updated July 6, 2012 by Per C.

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A computer that can load two operating systems is called what?

Dual core
Dual boot
Dual load
Dual launch
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