@SaiSekhar, MahasivaRavi (Philadelphia) - Thanks for the question and using MS Q&A platform.
This error message indicates that Azure Synapse Analytics is unable to list the contents of the directory where the external table is located. This can happen due to a number of reasons, such as incorrect file path, incorrect file format, or insufficient permissions.
To troubleshoot this issue, you can try the following steps:
Check the file path: Make sure that the file path specified in the external table definition is correct and the file exists in the specified location. You can also try to access the file directly from the storage account to verify that the file path is correct.
Check the file format: Make sure that the file format specified in the external table definition is correct and matches the actual file format. For example, if the file is a CSV file, make sure that the file format is specified as CSV in the external table definition.
Check the permissions: Make sure that the service principal or managed identity used to access the storage account has sufficient permissions to access the file. You can check the permissions by going to the storage account in the Azure portal and checking the access policies and shared access signatures.
If none of the above steps resolve the issue, you can try to create a new external table with a different file and see if you are able to query it successfully. If you are still unable to query the new external table, please do more details on the query used and error message which you are experiencing to investigate the issue further.
For more details, refer to MS Q&A thread addressing similar issue.
I hope this helps! Let me know if you have any other questions.