Did you guys ever figured what was the root cause? I am noting same issue.

Error: Site Settings is currently unavailable. DotNetNuke.Services.Exceptions.ModuleLoadException: Multiple controls with the same ID 'AdvancedUrlSettings' were found. FindControl requires that controls have unique IDs. ---> System.Web.HttpException: Multiple controls with the same ID 'AdvancedUrlSettings' were found. FindControl requires that controls have unique IDs. at System.Web.UI.Control.FillNamedControlsTable(Control namingContainer, ControlCollection controls) at System.Web.UI.Control.FillNamedControlsTable(Control namingContainer, ControlCollection controls) at System.Web.UI.Control.FillNamedControlsTable(Control namingContainer, ControlCollection controls) at System.Web.UI.Control.FindControl(String id, Int32 pathOffset) at DotNetNuke.ExtensionPoints.EditPageTabExtensionControl.BindAction(Int32 portalId, Int32 tabId, Int32 moduleId) at DesktopModules.Admin.Portals.SiteSettings.BindPortal(Int32 portalId, String activeLanguage) at DesktopModules.Admin.Portals.SiteSettings. (EventArgs e) --- End of inner exception stack trace ---

Error: Digital Asset Management is currently unavailable. DotNetNuke.Services.Exceptions.ModuleLoadException: Sequence contains more than one matching element ---> System.InvalidOperationException: Sequence contains more than one matching element at System.Linq.Enumerable.Single[TSource](IEnumerable`1 source, Func`2 predicate) at DotNetNuke.Modules.DigitalAssets.Services.Factory.get_DigitalAssetsController() at DotNetNuke.Modules.DigitalAssets.View..ctor() at ASP.desktopmodules_digitalassets_view_ascx..ctor() at __ASP.FastObjectFactory_app_web_c42pokud.Create_ASP_desktopmodules_digitalassets_view_ascx() at System.Web.UI.TemplateControl.LoadControl(IWebObjectFactory objectFactory, VirtualPath virtualPath, Type t, Object[] parameters) at System.Web.UI.TemplateControl.LoadControl(VirtualPath virtualPath) at DotNetNuke.UI.ControlUtilities.LoadControl[T](TemplateControl containerControl, String ControlSrc) at DotNetNuke.UI.Modules.WebFormsModuleControlFactory.CreateModuleControl(TemplateControl containerControl, ModuleInfo moduleConfiguration) at DotNetNuke.UI.Modules.ModuleControlFactory.LoadModuleControl(TemplateControl containerControl, ModuleInfo moduleConfiguration) at DotNetNuke.UI.Modules.ModuleHost.LoadModuleControl() --- End of inner exception stack trace ---