Nuget Feed - Forbidden 403

Octopus appears to be caching the credentials it uses to connect to my Teamcity nuget feed.

Originally i was connecting to an authenticated teamcity feed,and it was working for a while, but then it stopped (not sure why). Anyhow i changed the teamcity feed to be unauthenticated, but when i test the feed from octopus it gives me a 403 forbidden response, despite the fact i can access it in IE no problem. I have restarted both teamcity and Octopus with no joy, it would be helpful if i could see the request octopus is making out to teamcity, i have tried fiddler, but it doesn’t show the feed connection. Or are there any files i could delete that maybe caching credentials? I have also deleted the feed and created a new one, with no joy.

We are behind a corporate firewall, and have a proxy server, neither of these should be an issue though because octopus and teamcity are actually on the same box, so bypass the proxy and firewall.

The Teamcity feed is: http://teamcity:8085/guestAuth/app/nuget/v1/FeedService.svc/

Should have added we are using Teamcity 8.1.5 and Octopus 2.4.10.235.

If i go to the underlying url, it gives me this exception:
http://otctopus/api/feeds/feeds-34/packages?partialMatch=true&take=10
{
“ErrorMessage”: “The remote server returned an error: (403) Forbidden.”,
“FullException”: “System.Net.WebException: The remote server returned an error: (403) Forbidden.\r\n at System.Net.HttpWebRequest.GetResponse()\r\n at NuGet.RequestHelper.GetResponse(Func1 createRequest, Action1 prepareRequest, IProxyCache proxyCache, ICredentialCache credentialCache, ICredentialProvider credentialProvider)\r\n at NuGet.HttpClient.GetResponse()\r\n at NuGet.RedirectedHttpClient.GetResponseUri(HttpClient client)\r\n at NuGet.RedirectedHttpClient.EnsureClient()\r\n at System.Lazy1.CreateValue()\r\n at System.Lazy1.LazyInitValue()\r\n at NuGet.RedirectedHttpClient.get_CachedClient()\r\n at NuGet.RedirectedHttpClient.get_Uri()\r\n at NuGet.DataServicePackageRepository.GetPackages()\r\n at Octopus.Server.Web.Api.Actions.PackageSearchAction.SearchForPackagesNamedLike(IPackageRepository repository, String packageId, Int32 take) in y:\work\refs\heads\release-2.4\source\Octopus.Server\Web\Api\Actions\PackageSearchAction.cs:line 124\r\n at Octopus.Server.Web.Api.Actions.PackageSearchAction.Search(String feedId, String packageId, Boolean partialMatch, Boolean includeMultipleVersions, Boolean includeNotes, Boolean includePreRelease, Int32 take) in y:\work\refs\heads\release-2.4\source\Octopus.Server\Web\Api\Actions\PackageSearchAction.cs:line 58\r\n at Octopus.Server.Web.Api.Actions.PackageSearchAction.Execute() in y:\work\refs\heads\release-2.4\source\Octopus.Server\Web\Api\Actions\PackageSearchAction.cs:line 41\r\n at Octopus.Platform.Web.Api.Responder1.Respond(TDescriptor options, NancyContext context) in y:\\work\\refs\\heads\\release-2.4\\source\\Octopus.Platform.Web\\Api\\Responder.cs:line 162\r\n at Octopus.Server.Web.Api.OctopusRestApiModule.<>c__DisplayClass5.<.ctor>b__2(Object o) in y:\\work\\refs\\heads\\release-2.4\\source\\Octopus.Server\\Web\\Api\\OctopusRestApiModule.cs:line 47\r\n at CallSite.Target(Closure , CallSite , Func2 , Object )\r\n at Nancy.Routing.Route.<>c__DisplayClass4.b__3(Object parameters, CancellationToken context)”
}

For those who come across it this appears to be an issue with having Teamcity and Octopus installed on the same machine. There are two ways to resolve it, either install them on a separate machines, or as i did change the url of the feed to be localhost.
http://localhost:8085/guestAuth/app/nuget/v1/FeedService.svc/