I started to learn the Google Data API and encountered the problem that the first authorization request takes a very long time: 5-10 seconds, although subsequent requests pass quickly. And the examples for the Google Data API work the same way. I thought it was some kind of tricky defense, but everything turned out to be quite simple. WebRequest before the first request tries to automatically determine the proxy settings - this takes time. Autodetection of a proxy can be disabled by adding a session to app.config: