title: Nuget throwing 401 unauthorized error for no apparent reason
body: <p>I'm using VS2015 and Nuget to install external packages. Everything was working fine until today when Nuget started spitting out a:</p>
  
  <blockquote>
    <p>Response status code does not indicate success: 401 (Unauthorized)</p>
  </blockquote>
  
  <p>I tried looking around for a solution, everyone is suggesting to provide again the credentials, either from the console or the UI under tools -> nuget package manager -> manage nuget packages for solution</p>
  
  <p>No luck, what's going on here?</p>