Error refreshing datasource - "Unexpected number of disk files associated with database object."

Hi AndrewTobin ,

For such problems, if the backup file is encrypted, the password specified during the backup must be provided before you can use the file to restore the Analysis Services database. If the encryption key file is lost, you will never be able to decrypt the backup file. You cannot decrypt it using another generated CryptoKey.bin file (otherwise this would be a big security issue).
For more information you can refer to the following documentation.

Backup and Restore of Analysis Services Databases | Microsoft Docs

If the problem is still not resolved, please provide detailed error information and let me know immediately. Looking forward to your reply.

Best Regards,
Henry

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