2

It entirely depends on what you mean by cleaning out your computer ?

Formatting is a severe method of cleaning if you intend doing that - You can’t save a complete installation of avast as there are files in the avast4 folder, system folders and the registry entries.

You can download the latest version of avast and save a copy to CD, etc. o you don’t have to go on-line without protection. You can save the avast4.ini file if you have made any customisations to avast, you should save the email with your registration key.