AddSystem is a useless piece of software that you may find on your Mac even if you do not recall installing it. Although its name makes it sound as if it an important element, we assure you that it has no valuable features to offer. The name was probably chosen by its developers in order to mislead users into believing that it has anything to do with the Mac system. In reality, however, AddSystem is a Potentially Unwanted Program (PUP) that is often installed without the user's approval and permission.
It is important to add that AddSystem is not a harmful application – having it on your device is not a security concern. However, removing it is still recommended because it has the ability to modify the settings of Web browsers repeatedly. The PUP does this in order to promote low-quality search services by setting them as the browser's default homepage, new tab page, or search engine.
In addition to all this, it may also lock users out of their browser's settings, preventing them from undoing these changes. The proper way to remove AddSystem is to use an up-to-date Mac security scanner, which will ensure the full elimination of the PUP's components.