Azure Powershell module not connecting to any service

I created a free trial subscription in Windows Azure, and installed Azure Powershell module in a Windows server 2008 machine.

I download and import my publish settings file executing the following commands:

PS> Get-AzurePublishSettingsFile

PS> Import-Azure -PublishSettingsFile<my file's absolute path>

But then when I try to see my subscription's information I get the following error:

PS> Get-AzureSubscription

get-azuresubscription : Please connect to internet before executing this cmdlet

This error occurs every time I try to get some info related to my windows azure account.

What would it be? Is my publish settings file wrong? Do I have something blocking my PS and Azure connetion? Do I need to configure something on the Windows Azure server?

Thanks in advance