Updating fields in a prodected MS Word form

I have created a form in MS Word and want one of the form fields on the first page to repeat in the header of all subsuquent pages. I have bookmarked this field with a ref field, but when the document is protected it does not update unless I unprotect it, select the field and hit the update command. Does anyone know if there is a way to have the field automatically update with a tab, on exit, etc… Or if there is another way I can get the data in the form field to appear in the header of the subsuquent pages?