System.ArgumentNullException: Empty request body (Parameter 'Body') Status: 409, ErrorCode: BlobArchived

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Adding more information to the above response!

When exactly are you getting this error message?

"Status: 409 (This operation is not permitted on an archived blob.) ErrorCode: BlobArchived" error message indicates that you are trying to perform an action on a blob that is currently stored in the "Archive" access tier within Azure Blob Storage, which means you cannot directly modify or access the data in the blob without first rehydrating it back to a "Hot" or "Cool" access tier where it can be actively accessed Azure Blob Storage error codes

When a blob is archived, it is moved to a lower-cost storage tier, which restricts certain operations. Specifically, you cannot read, write, or delete an archived blob directly. To perform these operations, you need to rehydrate the blob by moving it back to a hot or cool tier.

This behavior is not related to the number of requests utilized but rather to the state of the blob being archived. If you need to access the blob, you will have to rehydrate it first. Here are the steps you can follow:

1. Rehydrate the Blob: Move the blob from the archive tier to either the hot or cool tier. This can be done using Azure Storage Explorer, Azure CLI, or Azure PowerShell.
2. Perform the Desired Operation: Once the blob is rehydrated, you can perform the read, write, or delete operations as needed.

Additional information :
An archived blob can be copied to a new blob within the same storage account. This will still leave the initially archived blob as is. When copying an archived blob as source the request must contain the header x-ms-access-tier indicating the tier of the destination blob. The data will be eventually copied to the destination blob.

You can follow the official doc and using REST API to copy archived files .
Access tiers for blob data.

Additional information: Rehydrating a blob from the archive tier can take several hours to complete. Microsoft recommends archiving larger blobs for optimal performance when rehydrating. Rehydrating a large number of small blobs might require extra time due to the processing overhead on each blob. A maximum of 10 GiB per storage account may be rehydrated per hour with priority retrieval.

To learn how to rehydrate an archived blob to an online tier, see Rehydrate an archived blob to an online tier.

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