If I had a virus, I'd know." The simple fact is that you don't know.

Modern malware can hide deep in your computer without raising red flags. There are some sneaky viruses that will remove other viruses so you don't get suspicious!

Click here to see my top free security software picks.

Porn chat 2013-20

Perhaps you notice a post on your Facebook profile you didn't write. If your friends and family click the link, they're infected and the virus spreads even further.

Keep an eye on your email "sent" folder and on your social network posts.

Just because a virus isn't disruptive doesn't mean it isn't dangerous.

It could be snagging your passwords, sensitive files or other vital information.

The "three-finger salute" lets you open up Task Manager.

This can show you what programs are causing trouble.

If nothing you do works, it could also be a hardware problem.

Most likely it's bad RAM or a failing power supply.

For decades, it's been making computer users miserable. In the early days, a virus would delete your files and spread to other computers.