When the Document Size Won’t Change
I tried to change the size of a document today, but only the pasteboard would change. Whatever I tried, the document size remained the same, even though the Document Setup size disagreed.
This stumped me for a moment, but then I realized what was probably happening. To understand, think about text formatting: Imagine that you have applyed a paragraph style to some text. If you select the text and change its font, you have applied a local override to the text. In other words, if you change the paragraph style definition, that selected text may not update to reflect that change because the local override is “on top” of the style.
In InDesign, the page size is sort of like a style. When you first create a document, the values (page size, etc.) in the New Document dialog box define the “default” size of that document. But in CS5 and later you can override those values, changing a document or master page size using the Page tool.
If you click on a page with the Page tool and change its size — even just a tiny bit — it will stay that size, even if you using File > Document Setup to change the underlying document size.
The only way to remove the “local page size override” is to click on the page with the Page tool, then use the Control panel (or Pages panel) to change the size of the page to match the document size again. Once it matches, InDesign forgets about the override and the page will follow the document setup dialog box again.