Hi Alex.

Ah, forgot the logs! It looks it doesn't like the fact we're running our site locally over https.

2017-09-08 12:45:06,824 [P11912/D83/T69] ERROR Umbraco.Web.Scheduling.KeepAlive - Failed (at "https://sitename.local:443/umbraco").
System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Net.WebException: The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel. ---> System.Security.Authentication.AuthenticationException: The remote certificate is invalid according to the validation procedure.
   at System.Net.TlsStream.EndWrite(IAsyncResult asyncResult)
   at System.Net.ConnectStream.WriteHeadersCallback(IAsyncResult ar)
   --- End of inner exception stack trace ---
   at System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
   at System.Net.Http.HttpClientHandler.GetResponseCallback(IAsyncResult ar)
   --- End of inner exception stack trace ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Umbraco.Web.Scheduling.KeepAlive.<PerformRunAsync>d__4.MoveNext()
 2017-09-08 12:45:07,638 [P11912/D83/T69] ERROR Umbraco.Web.Scheduling.ScheduledPublishing - Failed (at "https://sitename.local:443/umbraco").
System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Net.WebException: The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel. ---> System.Security.Authentication.AuthenticationException: The remote certificate is invalid according to the validation procedure.
   at System.Net.TlsStream.EndWrite(IAsyncResult asyncResult)
   at System.Net.ConnectStream.WriteHeadersCallback(IAsyncResult ar)
   --- End of inner exception stack trace ---
   at System.Net.HttpWebRequest.EndGetRequestStream(IAsyncResult asyncResult, TransportContext& context)
   at System.Net.Http.HttpClientHandler.GetRequestStreamCallback(IAsyncResult ar)
   --- End of inner exception stack trace ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Umbraco.Web.Scheduling.ScheduledPublishing.<PerformRunAsync>d__9.MoveNext()

We have <add key="umbracoUseSSL" value="true" /> set in the web.config but I'm guessing it doesn't like the local certificate we've created to run the sites in https on our local PCs.

I assume this won't be an issue when we eventually deploy to staging/production as we'll have a properly signed certificate rinstalled in those environments.

Cheers

Chris