Shift to Read Only Macro

Change ActiveWorkbook to ActiveDocument and Workbooks to Documents.

Use:

Dim fullname As String
With ActiveDocument
    If .ReadOnly = True Then
    fullname = .fullname
    .Close
End With
Documents.Open fullname, ReadOnly:=False

The following seems to work OK as a toggle macro...

Sub ReadOnlyToggle()
' http://answers.microsoft.com/en-us/office/forum/office_2010-word/shift-to-read-only-macro/33c5309f-5d3f-490d-acc0-d64ac149f6ae
' Thanks to Doug Robbins 9/2014
  Dim fullname As String
 
  If ActiveDocument.ReadOnly = True Then
     With ActiveDocument
        fullname = .fullname
        .Close
    End With
    Documents.Open fullname, ReadOnly:=False
    Exit Sub
  End If

  With ActiveDocument
    'New file?
    If .Path = "" Then Exit Sub
    'Already readonly?
    'Save the path\file name of the current file
    fullname = .fullname
    'Close it, ignore changes
    .Close False
  End With
  'ReOpen readonly
  Documents.Open fullname, ReadOnly:=True


End Sub