Hey Vaibhav Gadewar,
The path to connect to the data source is using a mapped path. Tableau Server uses the Run As user account to authenticate a data source. Because the Run As user account cannot access resources that have been authenticated in the security context of another user, it cannot use the mapped path.
You should try to update the data connection(s) in Tableau Desktop to reflect the UNC path to the Excel workbook, instead of a file path that includes a mapped drive letter, and republish the workbook.
Lénaïc RIÉDINGER, Global Community Engineer Tableau
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