Object reference not set to an instance of an object when attempting to Configure App URLs

I've created an App Catalog, and can go into all of the App Management pages in Central Administration except for Configure App URLs.  If I click on that I get: "Object reference not set to an instance of an object".  I've included the log entry below.  I have the app management service running and have rebooted the server.  Any ideas on what to do?

Thanks!!

11/20/2012 16:24:51.45     w3wp.exe (0x03D8)                           0x0A50    SharePoint Foundation            General                           8nca    Medium      Application error when access /_admin/ConfigureAppSettings.aspx, Error=Object reference not set to an instance of an object.   at Microsoft.SharePoint.ApplicationPages.ConfigureAppSettingsPage.DisableChangesAndDisplayMessage()     at Microsoft.SharePoint.ApplicationPages.ConfigureAppSettingsPage.OnLoad(EventArgs e)     at System.Web.UI.Control.LoadRecursive()     at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)    9521e39b-7271-2057-9899-bdc3027a47e8
11/20/2012 16:24:51.46     w3wp.exe (0x03D8)                           0x0A50    SharePoint Foundation            Runtime                           tkau    Unexpected    System.NullReferenceException: Object reference not set to an instance of an object.    at Microsoft.SharePoint.ApplicationPages.ConfigureAppSettingsPage.DisableChangesAndDisplayMessage()     at Microsoft.SharePoint.ApplicationPages.ConfigureAppSettingsPage.OnLoad(EventArgs e)     at System.Web.UI.Control.LoadRecursive()     at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)    9521e39b-7271-2057-9899-bdc3027a47e8