Azure subscription issue

Hi, I need to create a VM using Windows Azure Powershell. I Have given this subscription detail,

Set-AzureSubscription -SubscriptionName "*subname*" -CurrentStorageAccount "*storagename*"
Select-AzureSubscription -SubscriptionName "*subname*"

even then Im getting the below error. 

New-AzureVM : You MUST specify a certificate. Call Set-AzureSubscription and Select-AzureSubscription first.
At line:33 char:1
+ New-AzureVM -ServiceName $service -AffinityGroup $AG -VMs $MyDC
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : CloseError: (:) [New-AzureVM], ArgumentException
    + FullyQualifiedErrorId : Microsoft.WindowsAzure.Management.ServiceManagement.IaaS.PersistentVMs.NewAzureVMCommand

New-AzureVM : The path variable 'SUBSCRIPTIONID' in the UriTemplate must be bound to anon-empty string value.
Parameter name: parameters
At line:33 char:1
+ New-AzureVM -ServiceName $service -AffinityGroup $AG -VMs $MyDC
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : CloseError: (:) [New-AzureVM], ArgumentException
    + FullyQualifiedErrorId : Microsoft.WindowsAzure.Management.ServiceManagement.IaaS.PersistentVMs.NewAzureVMCommand

Can you please guide.