Access to Amazon EC2 Windows instance via Remote Desktop

  amazon-ami, amazon-ec2, remote-desktop, windows

I’m new to AWS EC2 and I’m trying to access to a windows instance (it’s an image created from another instance),

But when I click on Get password in RDP section, i got this message:

Error message

The instance was running since yesterday so why I still have this message? is this something related to missing configuration?

Thanks for your help!

Source: Windows Questions