Shown here is Iain Hamilton's suggestion for processing 
all items in a list. It only uses a single batch file.
It uses an input file called userlist.txt and processes 
the last line first.

:repeat
set usersname=
for /f "eol=; tokens=1*" %%i in (userlist.txt) do set usersname=%%i
if "%usersname%"=="" goto ender
type userlist.txt| find /v "%usersname%"> userlist1.TXT
copy userlist1.txt userlist.txt
goto repeat
:ender

This method eliminates the need for fragments (or calling 
other batch files.) and doesn't need any 3rd party utilities.
Since this is an NT batch file, it won't work on Win9x.