There are indeed cases when spyware infects a computer with little to none interaction from the computer user. Most of the time however, social engineering is used to spread Malware. What is social engineering? Well, the closest thing in real life is conning. You are being conned in installing spyware or following a link that leads to such an installation.
How To Recognize Social Engineering Schemes
Just like good old fashion cons, social engineering schemes and spyware relies on deception and building a misplaced trust. There are always signs however that someone is trying to trick you.
The easiest way to decide on whether somebody is trying to infect with spyware is to keep the next statement in your head: ‘If it sounds too good to be true, than it probably is’. The variety of offers found on the web and the fact that some of these are actually legitimate makes the whole thing much more difficult though. An approach to solving such dilemmas is to do a bit of digging and see what other readers and review sites have to say about it. Simply search the name of the company or the offer in a good search engine and attach the word scam in your query.
Another way to detect e-mail fraud and thus prevent spyware is to look whether the e-mail received was also sent to other addresses. This is not something bad in itself, but if your e-mail address is firstname.lastname@example.org and you see other addresses like email@example.com than you are dealing with a scam, someone sent this e-mail from a spyware infected computer via a brute force attack. Needless to say, you should mark that e-mail as spam and forget about it.
To avoid being a part of such a scam, it is recommended that computers should be regularly scanned for infections from spyware or Malware. You can download a copy of Systweak AntiSpyware for a Free Malware Scan.