PowerShell Add-AzureAccount and authentication_failed

Hello,

I was using the Add-AzureAccount powershell command to log on to my azure subscriptions from powershell. However recently this command started to fail and I cannot log on again. The error message is

"Add-AzureAccount : authentication_failed: The system cannot locate the resource specified."

The Add-AzureAccount command opens a browser dialog with text "The system cannot locate the resource specified". The log on screen does not appear.

What's wrong?

This is what I'm expecting to happen

http://michaelcollier.wordpress.com/2013/10/28/windows-azure-ad-authentication-support-for-powershell/

Thanks