Getting an error while opening the Cloud Shell

Hello KARTHIK REDDY THATIKONDA, the error you're facing while launching cloud shell indicates a broken or incomplete cloud shell setup, often due to missing subscription context or failed storage provisioning. Cloud shell needs a valid azure subscription with permissions to create a storage account the first time it runs.

Microsoft says in this MS document that "You can't create the Cloud Shell storage account when using a Microsoft Entra subscription."

This confirms cloud shell cannot work without a valid Azure subscription that allows resource creation like storage accounts. From your error, it looks like the subscription id is blank which means cloud shell couldn't resolve which subscription to use.

The same document also says- "When creating the Cloud Shell storage account for first-time users, it's unsuccessful due to an Azure Policy assignment placed by your admin."
This matches cases where cloud shell fails to initialize due to policy restrictions likely if the subscription doesn’t allow resource creation.

Even though you mentioned you've registered cloud shell, it’s possible that your subscription does not allow resource creation (common in sandbox/Entra-only setups) or cloud shell provisioning failed halfway (no storage account was created)

You can troubleshoot all these from your end and see which is missing from my above suggested points. I would recommend you first check here- https://portal.azure.com/#view/Microsoft_Azure_Billing/SubscriptionsBlade

Make sure your subscription is enabled, and not in a disabled or deprovisioned state.
Please note, if you're using Microsoft Entra-only subscription (common in test tenants), it won’t work. You'll need a full Azure subscription. If storage wasn't created earlier, recreate it. Check if a resource group named something like cloud-shell-storage-somelocationNameexists. If it doesn't exist, then that is the cause.

Also, have you tried to restart/reset your cloud shell

Please check all these and let me know if you have any further query. Thanks.