Use Microsoft account in 8.1 enterprise

Hi all

I recently created an VM with Windows 8.1 enterprise and want to play with it. I followed this guy's way to created account:

http://social.msdn.microsoft.com/Forums/windowsazure/en-US/21cab7c1-cb2c-4d4e-9e4d-dfe8cdce520d/action?threadDisplayName=windowsazure&forum=WAVirtualMachinesforWindows

But still can't sign in with DRP, it's said my credential doesn't work .

Could anybody tell me what's wrong with it.