from the wonderful said:
Yes they are all required. Windows XP is based on Windows 2000, which was
based on Windows NT. Since Windows NT was a multi-user operating system and
each user can have their own Windows configuration, the system needed to be
able to store the configurations.
There are several "default" users which Windows XP creates. The ones I know
about are:
default user --- The general user account, which "seems" the be "linked" to
the current logged in user account.
'default user' is used as a 'template'; whenever a new user account is
generated it start from 'default user' values.
all users --- This is where there desktop configuration (desktop icons
and start menu) settings are store. These
are the same "base" for all defined users on this
There is only one valid version of 'default user' and 'all users', for
any one installation of XP. Other copies which have 'windows, .<machine
name>, .000, etc appended to them get created if you re-install(ed) XP,
or if XP is unable to load the original profile for some reason, or if
you have some other NT OS running on the same partition (horrible idea).
You can use 'set' command in a CMD window to find out where =your=
%userprofile% setting points, but it's a bit more difficult to figure
out which of the 'default user' or 'all users' profiles are real and
which are obsolete. If you try to open 'all users\ntuser.dat' and it is
locked, then it's a pretty good bet that that is the profile currently
in use for 'all users'.