Hello @MUSTAFA AHMAD MUSTAFA AL-HUNAITI,
Thanks for the question and using MS Q&A platform.
As per the testing from my ending, the above Secure a data warehouse in Azure Synapse Analytics learning page working as excepted.
From the error message which you are experiencing is a problem with your system which you are using. You may checkout this thread which addressing similar issue.
Hope this helps. Do let us know if you any further queries.
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