Value cannot be null. Parameter name: subscriptionId. Although it's not empty

Hello,

I have an issue when i call a powershell script from asp.net website. Although the script runs successfully when i open azure powershell CLI.

The error is:

Import-AzurePublishSettingsFile "MyPublishSettingsFilePath"
CategoryInfo          : CloseError: (:) [Import-AzurePublishSettingsFile], CryptographicException
 FullyQualifiedErrorId : Microsoft.WindowsAzure.Commands.Profile.ImportAzurePublishSettingsCommand
 
System.ArgumentNullException: Value cannot be null.
Parameter name: subscriptionId

BTW, I run Get-AzureSubscription command on azure powershell CLI and i could see that there're a SubscriptionName and SubscriptionID.

Any ideas? 

Thanks in advance,

Marwa Ahmad