When using 'Move to ... namespace' quick fix to cure 'Namespace doesn't correspond to file location quick fix' on aspx files, ReSharper correctly updates .aspx.cs and .aspx.designer.cs files but doesn't update aspx file itself. If you open the admin/admin.aspx.cs file you should see a resharper hint for the namespace MyCompany.MySite suggesting ot rename it to MyCompany.MySite.Admin. When using this refactoring, the admin.designer.cs file get's updated, but the "inherits" tag in the @page directive in admin.aspx does not.