Word C# accessor methods (get_*, set_*)

[Rob Stewart]

Is anyone able to give me a high level overview of when to expect and
use accessor methods in the Word object model?

I am trying to set, for example, the "Different Odd & Even Page
Header" property in a Word doc.

I am trying ...
ActiveDocument.PageSetup.OddAndEvenPagesHeaderFoot er = 1;

.... but get error msg
System.ArgumentException: The parameter is incorrect,
at Microsoft.Office.Interop.Word.PageSetup.set_OddAnd EvenPagesHeaderFooter
(Int32 prop) at <...goes on to provide code location...>

Should I be using an accessor method in this code, or am I just
missing something ... if so, is there an example available?

Thanks for any assistance,
Rob