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Description:
While importing the corrupted excel file, currently we will show the "Unsupported file" dialog, like below,

And, we need to send the exception details from the server side and receive the details in a callback function and show it in a client side sample.
For example, if the excel file throws the exception while opening in a server, we need to send the details of the exception like "Length cannot be less than zero. (Parameter 'length')" from the server and receive the details in a callback event like openFailure in the client side and show the exception details.