Short Answer:

• The UC error is almost always caused by the wrong identity being used in the Storage Credential / External Location, even if IAM + ACLs look correct.

• The VM failures are typically quota + regional capacity issues in UK South, especially for older families like DSv2/F-series.

• Fixes:

  • Re-check the Storage Credential → External Location chain

  • Increase quotas for a modern VM family

  • Or try a newer region with better capacity

I will try to write step by step.