Check the 'Editing restrictions' checkbox. Select 'Filling in forms' from
the dropdown (which becomes enabled when you check the box). 'Select
sections' will appear beneath the dropdown. Click and select section one.

If you must do this in a macro, you have to set the ProtectedForForms
property for each section -- or at least for those that should *not*
be protected -- and then you also have to turn on the protection:

   ActiveDocument.Sections(1).ProtectedForForms = True
   ActiveDocument.Sections(2).ProtectedForForms = False
   ActiveDocument.Protect Type:=wdAllowOnlyFormFields

The first of these lines is optional, because the .Protect method
assumes that all sections should be protected unless you specifically
state otherwise.

To do it without a macro: First insert at least one section break in
the document (you've already done this). Then open the Protect
Document task pane (what you called a popup, but it isn't that), check
the box under Editing Restrictions, and select "Filling in forms" in
the dropdown. At that time, a blue link "Select sections..." appears
under the dropdown. Click that link to get a dialog where you can
uncheck Section 2.

--
Regards,
Jay Freedman
Microsoft Word MVP        FAQ: http://word.mvps.org
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