So this is a quick blog for a frustrating issue, that is actually very easy to resolve.
If you are on Windows Server 2012, and you’ve had to reinstall WSUS for any reason and receive the following error in your tmp log after attempting to finalize the installation:
2013-02-20 16:04:17 Creating default subscription.
2013-02-20 16:04:17 Instantiating UpdateServer
2013-02-20 16:04:19 CreateDefaultSubscription failed. Exception: System.Net.WebException: The request failed with HTTP status 503: Service Unavailable.
at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall)
at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters)
at Microsoft.UpdateServices.Internal.ApiRemoting.GetServerVersion()
at Microsoft.UpdateServices.Internal.DatabaseAccess.AdminDataAccessProxy.GetServerVersion()
at Microsoft.UpdateServices.Internal.BaseApi.UpdateServer.CreateUpdateServer(String serverName, Boolean useSecureConnection, Int32 portNumber)
at Microsoft.UpdateServices.Internal.BaseApi.UpdateServer..ctor(Boolean bypassApiRemoting)
at Microsoft.UpdateServices.Setup.StartServer.StartServer.CreateDefaultSubscription()
2013-02-20 16:04:19 StartServer encountered errors. Exception=The request failed with HTTP status 503: Service Unavailable.
2013-02-20 16:04:19 Microsoft.UpdateServices.Administration.CommandException: Failed to start and configure the WSUS service
at Microsoft.UpdateServices.Administration.PostInstall.Run()
at Microsoft.UpdateServices.Administration.PostInstall.Execute(String[] arguments)
It’s most likely an IIS issue.
Open the IIS console, delete the WSUS Site, and perform the post installation tasks again.