True if the styles in the specified document are updated to match the styles in the attached template each time the document is opened. Read/write Boolean.
Example
This example enables the option to update document styles for all open documents and then closes the documents. When any of these documents is reopened, changes to the styles in the attached template will automatically appear in the document.
For Each doc In Documents
doc.UpdateStylesOnOpen = True
doc.Close SaveChanges:=wdSaveChanges
Next doc
This example disables the option to update document styles so that changes made to the styles in the attached template aren't reflected in Report.doc.
Documents("Report.doc").UpdateStylesOnOpen = False