If the Azure VM creation failed due to an empty region dropdown, it is likely that the region selected does not have any available virtual machine sizes. To resolve this issue, you can either choose a different region where the desired VM size is available or select a different VM size that is available in the desired region. To check the VM sizes that are available, click Settings, show "Azure" types, and check the Azure VM Size records for the requested region. If the "Restricted" column's value is "true", this VM size is not available for the subscription.
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