Automatically enter User Name to all word documents

[JRubinstein]

I am the network manager of a school and am trying to ensure that when a
student opens a new word document they will automatically have their names
entered on the footer.

I have tried simply altering normal.dot to auto-enter the author, but when
logged in as student this displays my name.

I have created a macro which automatically enters the student's name but if
I make this run on AutoExec it fails because there is no document available
to enter the information into. If I set it to run on AutoNew, then it will
not run unless the student starts a "new" document, in other words the first
document they get when they double click on the "Word" icon doesn't have the
information although if they go on to create a new document that one will
have.

I'm sure this is a standard idea, what am I missing?

Thanks in advance.