Hi Andrew Scott,
Thank you for contacting the Q&A forum.
The sandbox is inaccessible for this module “Describe the core architectural components of Azure” and where this might be because of temporary errors, our backend team is however actively working to ensure that it is rectified in the shortest time possible. We will be notified through the module as soon as the sandbox is functional. In the meantime, you can either go ahead with the training without components or you can make use of the Azure Free Trial membership to go ahead with the training.
If you continue to face issues, please let us know in the comments. We are here to help.
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