Hi Naveen,
It's most likely not Orbeon Forms that answers with a 401, but some authentication mechanism that you have in front of Orbeon Forms. (In fact, I don't think that Orbeon Forms ever answers 401 to Ajax requests. It only answers 401 to some requests for web pages to Form Runner.) So I would look at the request in more details, check logs on the server, and figure who answers with a 401.
Alex
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