# The HTTP request is unauthorized with client authentication

**URL:** <https://discussions.flightaware.com/t/the-http-request-is-unauthorized-with-client-authentication/18372>\
**Category:** AeroAPI\
**Created:** [April 25, 2016, 4:38pm UTC](https://discussions.flightaware.com/t/the-http-request-is-unauthorized-with-client-authentication/18372 "2016-04-25T16:38:07Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![SharadShitole](https://avatars.discourse-cdn.com/v4/letter/s/8c91f0/32.png) [@SharadShitole](https://discussions.flightaware.com/u/SharadShitole)\
**Post date:** [April 25, 2016, 4:38pm UTC](https://discussions.flightaware.com/t/the-http-request-is-unauthorized-with-client-authentication/18372/1 "2016-04-25T16:38:07Z")

</div>

I am getting below Error while accessing Flight Aware API

"The HTTP request is unauthorized with client authentication scheme ‘Anonymous’. The authentication header received from the server was ‘Basic realm=“FlightXML2”’.

While inner exception gives me message as below.

“The remote server returned an error: (401) Unauthorized.”

---

<div class="post-metadata">

**Author:** ![adimic](https://avatars.discourse-cdn.com/v4/letter/a/ed655f/32.png) [@adimic](https://discussions.flightaware.com/u/adimic)\
**Post date:** [April 25, 2016, 10:29pm UTC](https://discussions.flightaware.com/t/the-http-request-is-unauthorized-with-client-authentication/18372/2 "2016-04-25T22:29:30Z")

</div>

You are probably not passing your credentials (username and password) the right way.  
Have you looked at the example codes on this page? [flightaware.com/commercial/flig … ation2.rvt](https://flightaware.com/commercial/flightxml/documentation2.rvt)  
What language are you using?