Get-AzureRmSubscription returns 'WARNING: Unable to acquire token for tenant 'Common''.

Hi there,

I'm trying to login via azure powershell to my subscription, but Login-AzureRmAccount isn't finding my tenantid or subscriptionid from within my organization.   Outside it's fine - we can login correctly, but when logging in within the log I can't login at all:

PS I:\> Login-AzureRmAccount

Environment           : AzureCloud
Account               : <AccountName>
TenantId              :
SubscriptionId        :
CurrentStorageAccount :

PS I:\> Get-AzureRmSubscription
WARNING: Unable to acquire token for tenant 'Common'
PS I:\>

If I do the same commands from outside the organisation it works fine.

This also happens even if I login as a non-corporate windows live Id account (i.e. I use a personal account that has nothing to do with my company).

I'm guessing it's authenticating against my domain account somehow, but it's very odd.  Curiously, Add-AzureAccount works fine:

PS I:\> Add-AzureAccount
Id                             Type       Subscriptions                          Tenants
--                             ----       -------------                          -------<AccountName>   User       <blah>                                 <blah>

PS I:\> Get-AzureSubscription

SubscriptionId            : <blah>
SubscriptionName          : Microsoft Azure Enterprise
Environment               : AzureCloud
DefaultAccount            : <AzzountName>
IsDefault                 : True
IsCurrent                 : True
TenantId                  : <blah>
CurrentStorageAccountName :

I'm at a bit of a loss why I can't login to AzureRm, especially as all of our services are in Resource Manager mode. :(

Thanks!