Potentially unwanted program
A potentially unwanted program (PUP) is software which is generally installed without the user's knowledge or consent. This is usually a demo version of some program they are attempting to sell, which is bundled with another install. When someone goes to install a certain desired program, the PUP is installed as well, with or without the user's consent. These unwanted add-ons are also sometimes called bloatware, since they can fill (bloat) a computer system with useless software. People would be well advised to watch carefully what is going on when downloading software. The screens associated with software downloads are often set to "yes" for these things, and the ways to decline such installations are often obscure. You only install a given piece of software once—it's worth taking the time to pay close attention to what is going on.
Kinds of Potentially Unwanted Programs
- Adware (Like Superfish) - Insert advertisements into web pages you view, or even starts popup ads in your computer system itself
- Crippleware - Installs a program which can do little if anything. This will usually nag the user to buy the full version so that they may actually use it. The most common kinds are anti-malware and system optimization programs.
- Mirror/Local Proxy - Mirrors or redirects all internet traffic through itself so it may build a profile of the user, which may be used for targeted marketing or sold
- Web browser Hijacking - Forcibly alters browser settings to earn the distributor money, usually by changing the home page and/or default search engine. This sort of thing is very common. Browser addons are also sometimes installed, though these can often be classified as Adware and/or Spyware.
- Dialer - A largely out-of-date attack intended for dial-up internet connections (or now, Cellular phones) which dials out to unwanted destinations for the purpose of wasting the owner's data transfer allowance.
Since the Adobe Flash Player is so common, perhaps Adobe offers one of the best examples. They have been attaching PUPs to their Flash Player and Shockwave products for years. This is one of the ways Google Chrome took over the web browser market.
Another example is the program "Freemake Video Converter," which is actually a fine piece of software by itself. However, the installer contains PUPs, which the user may want to avoid.
Figure 1 shows the initial screen after starting the download and installation process. It is quite common for people to select the "express" installation rather than the "custom" one. Custom installations often involve complex decisions that a casual user would not be able to make. That's why the "standard" or "express" installation is usually a good idea, and is usually recommended.
But read the fine print! It will install adware, and hijack the user's browser if they don't select "Custom".
After they choose "Custom" and click "Next", more checkboxes will come up, as in Figure 2. They need to uncheck the two items before clicking "Next".
At this point Figure 3 comes up. They're still trying to install bloatware. This time it's an "Advanced ScreenSnapshot" program. Once again, users should pay attention to what the installation process is doing, and select "Custom installation", "advanced" though that may be.
After they choose "Custom", users get Figure 4, with another checkbox that they should clear before clicking "Next".
And now users reach Figure 5. They just don't give up—more utilities are offered. "Speed Up your PC" and "remove clutter" utilities are ubiquitous across the internet. (And why anyone would want to increase their startup time by 75% is a mystery.) The "Extend your battery life" trick presumably just sets the user's power profile to the "low power" option. That is a standard option that Windows offers when the computer is first started.
So users must clear that checkbox. Then, when they click "Next", the software that they want will be installed.