More specifically, when you install a program on your computer:

In simple words, DO NOT INSTALL ANY IRRELEVANT SOFTWARE that comes with the software installer of the program that you want to install.

For that reason, you must always pay attention at the installations options for any program you install on your computer, because most software installers contain additional software that you never wanted to install. PC Cleaner Pro, was probably installed without the user's notice because it is commonly bundled inside other freeware software which are downloaded -and installed- from known internet sites like “ (CNET)”, “”, etc. Another symptom upon infection, is that your computer speed may be slowed down due to malicious programs running on the background. When your computer is infected with PC Cleaner Pro, then it continuously displays messages that your computer is under security risks and you must buy the program to fix them. Technically PC Cleaner Pro is a virus and is categorized as a Rogue program, that may contain and install other malicious programs on your computer, like malware, adware, toolbars or viruses.

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