Hi @Sean Owen
I'm sorry, that's a stressful one. Only Microsoft support can look at backend migration logs, so a support case is the only route for that part. Before you open it, one thing from Microsoft's own GPv1 retirement FAQ is worth knowing: the upgrade is designed not to delete or move data, and for auto-upgrades it says data is preserved but access can be temporarily impacted. So it's worth confirming whether the blobs are really gone or just not showing up yet.
Here's what I'd do, in this order, without changing anything in the account:
- Pause writes. Stop any app or job that writes to or cleans up those containers, so nothing overwrites or removes more data while you investigate.
- List the container directly. Use Azure Storage Explorer or
az storage blob list against the container, not your app. If the files show up there, the issue is in how the app reads them, not data loss.
- Check the Activity log on the storage account for the migration window. Look for delete operations, and see which identity made them.
- Open a support case right away (Help + support > Create a support request), with the highest severity your plan allows. Describe it as data missing after the automatic GPv1 to GPv2 upgrade. Include the account name, the container names, and the approximate time the files were last seen. Share those only inside the ticket, not here.
- Once it's sorted, turn on blob soft delete and versioning. It won't recover past deletions, but it protects you next time.
When you list the container with Storage Explorer, do the missing files show up there, or are they absent too?
If this resolved your issue, please consider accepting it as the answer. If the files are missing in Storage Explorer as well, let me know and I'll be happy to keep helping.
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