Clean install definition
A clean install is a new installation is where the previous version of the application or operating system is eradicated and then replaced by the latest version. Installing an operating system for the first time on a new computer is also a clean install.
Real clean install examples
Every time a new user gets a previously used computer, a clean install is the best option to wipe the hard disk.
Whenever all previous troubleshooting has failed to fix software problems, a clean install is most likely to fix the problem.