Most people's computers get exploited in only a handful of ways. Among the most popular methods is tricking people into downloading and running Trojans. Often, unsuspecting users get socially engineered into running a malicious file or app by following a link in email or visiting a website.
It can be tough to spot the fake stuff, so here's what you should watch for.
1. Emails with links to suspicious downloads
Yes, you can be sent legitimate info in emails, but 99 percent of it is either garbage or malicious. Due to antispam measures, most vendors now use methods other than email to advertise and spread their software. You know better. Don't fall for this.
2. Promos for antimalware software, disk cleaners, and optimizers
Find out what your antivirus program looks like when it's scanning for malware, so when you see the fake one, you'll know the difference. In general, real antivirus programs will not pop up when you visit a website -- then begin scanning your computer and claiming you're infected with dozens of viruses. Real antivirus software pops up and tells you it has blocked one malware program. The fake stuff usually also wants to scan your whole computer.
Malware writers also like to hide their rogue creations in fake disk compressors and optimizer programs. Don't install computer optimization programs. Most of them, including the real stuff, are junk.
3. Websites that ask you to install software
It's the rare website that asks you to install an app or a plugin to enjoy its content. Most often the site has either been created or modified by hackers to trick you into installing software. Want to stay uninfected? Don't install software from websites unless you're 100 percent sure the software is needed and is a legitimate product.
This includes Java, Adobe Acrobat, and Flash. Be especially suspicious if you know you've already installed what is ostensibly required -- and absolutely reject the install if the link doesn't point to the legitimate vendor's website. Legitimate vendors do not let other websites install their software. (The exceptions are legitimate proxy sites such as Download.com.)
4. The program you downloaded doesn't do what it said it would
Let's say you've followed a request to download and run software so that you can view an "encrypted" file. But after doing so, you can't read the purported (bait) document. Or you downloaded an app that was supposed to speed up your computer, but it doesn't work. Some Trojan horse programs follow through with the promised action, but most don't.
5. Your computer is much slower after installation
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