There are some special pages in SharePoint 2010 which do not use any master page. You should be aware of these pages to avoid bad user experience while branding your site. Following is the list of those pages:
AccessDenied.aspx : Displays, if user does not have permission to perform respective action.
Confirmation.aspx : Displays, to confirm that your intended operation has been completed successfuly.
- Error.aspx : Displays, whenever an error occurs while processing the page.
- Reqacc.aspx : Displays, whenever user need to requests the access to certain area of SharePoint site.
- SignOut.aspx : Displays, when user signs out.
- WebDeleted.aspx : Displays, to confirm that the site has been successfuly deleted.