When we say "clean machine" we are not talking about
the outside of your computer. We are talking about all of the
files on your computer's hard drive(s).
When you buy a new computer, it usually comes loaded with an
operating system such as Microsoft Windows. It may come loaded
with application programs, utilities, games and even data.
The operating system and all programs and data on your computer
form a collection of files that are contained on the computer's
hard drive.
As you add programs, remove programs, change configurations,
create documents, send and receive email, view Web pages and create
favorites, etc., the collection of files is being changed.
Problems occur when something is wrong with the collection of
files. It could be missing files, incorrect versions, corruption
of file contents, etc.
The general idea of a "clean machine" is one that is
not loaded with things you don't need to get your work done.
As you can tell, just using your computer changes what is on
it. Often when a person has problems with their computer they
go on a "digging and clicking" mission, changing things
that they do not know about.
Other times people will install new versions of software hoping
that it will solve the problem. Often times the result is a big
mess that is similar to a ball of tangled fishing line.
Sometimes its better to just wipe out the whole contents of the
hard drive after backing up all data, rather than trying to untangle
the mess that has been made. Next would be a reinstallation of
the operating system, applications and data. This would be the
"start clean" part. Starting clean can be a lot of work
if you already have a mess but it is often necessary rather than
spending days or weeks trying to make everything work without
successful results.
Not adding stuff or changing things unnecessarily would be the
"stay clean" part. Resist the temptation to add things
you don't need to the computer you depend on. Use an old computer
or one you do not depend on to do your experimenting.
Following this advice will improve reliability and security and
save you lots of headaches and downtime.