Hello Nicole Crowley,
Thank you for posting your query here!
I understand that you are moving blobs from one storage tenant to another using the .net SDK and getting the error "(This request is not authorized to perform this operation.)\r\nErrorCode: CannotVerifyCopySource"
There can be a lot of reasons users can’t read/write content on Azure storage containers and access blob objects on storage accounts.
First, please try to change Azure Storage's security and network settings:
Go to Azure portal and find the storage account. And then go to Networking tab in Security + networking group.
If the blob storage is public, you can configure the firewall and virtual networks to allow access from all networks.
If the storage is not public, you can create a virtual network and then only grant access to your resources in the specific network. You can also configure specific IP address.
Refer to page for more details about how to make these settings: https://docs.microsoft.com/en-us/azure/storage/common/storage-network-security?tabs=azure-portal
You may also check and assign a storage contributor role, as without a contributor role, it’s not possible to read/write data on a storage account, which might be causing the error.
Please go to Storage account -> Access Control (IAM) -> Add -> Add role assignment, then add Storage Blob Data Contributor/ Storage Blob Data Owner to your login account.
Also, please do confirm that the SAS token has not expired. If it has expired, you will need to generate a new SAS token with a valid expiry date.
Kindly let us know if you have any further queries. I’m happy to assist you further.
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