export app from a backend server

[eazoury]

We are developing a .net framework  to send api requests to sensetst. It consists of a backend and frontend. 

When trying to export an app using the api call from the backend  : app/id/export/uuid?sskipdata=true I get correctly the download link .

However when trying to get the stream from the download link  :

var restClient = new Qlik.Sense.RestClient.RestClient(getSenseUrl(env));

restClient.AsNtlmUserViaProxy(new NetworkCredential(false));

//restClient.AsNtlmUserViaProxy(new NetworkCredential( Settings.Default.SVNUser, Settings.Default.SVNPassword));

return restClient.GetStream(ticket.downloadPath);

When run locally it does work , however when published on the server  I can't find a way to connect to sensetst using the frontend user windows authentication credentials.

Any help ?