When you insert a new page into a Microsoft Office Visio 2007 or Microsoft Office Visio 2003 drawing, the Background property has a blank entry. If you select Nonefor this property, you cannot re-select the blank entry.
Additionally, you may experience the same problem if you view the Page Properties tab under Page Setup.
This problem occurs when you hide the background page by setting the UIVisibilty cell and set it to UIVHidden on the Page Properties section in the Shape Sheet window for the background page. After you hide the background page, you cannot make the background page visible again. However, as long as you do not set the Background property for a new page to None, the existing background will be applied to the new page.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section of this article.