Computer barnacle - Definition and Overview

Computer barnacles are data collecting or advertising software which are often installed with the user's knowledge and consent, usually as part of a larger installation. These programs often degrade system performance, abuse network resources, interfere with network connectivity and are often designed to be difficult or impossible to uninstall. Barnacles can be classified as a special type of spyware.

Because the user agreed to install these programs on their machine, privacy enforcement programs will often overlook them. Some computer barnacles require that the user fill out an online form before they are allowed to uninstall the program. Depending on the overall health of the system, this might be impossible. Others will set up intentionally confusing or counterintuitive uninstallation wizards, in order to prevent users from removing them.

Barnacles often make use of Layered Service Provider technology in order to redirect information from a computer's TCP/IP stack. When they are removed, they can corrupt the workings of the internet protocols, and damage the system's network functionality, prompting a reinstallation of the TCP/IP stack.