It would have been helpful had you said what you wanted the macro to do. Given the lack of context, I understood you to want a macro to update the document content, not just the fields. In any event, your macro:
a) would have to be added to either the document template (assuming all documents use the same template; otherwise to multiple templates) or to every one of the documents, introducing macro security issues; and
b) will not do the same as checking the 'update automatic links at open' option, which only needs to be done once, not every time a document is opened.
With the 'update automatic links at open' option checked, that shouldn't be necessary. Have you tried checking it, then closing & re-opening one of the target documents?
You can't control how anyone else sees the document - that depends on how they have Word configured.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]