Hi @Nikhil Desai,
You will need to grant permissions on the Analysis Services instance. Each database object will have roles that provide a given level of permissions (read or read/write), and each role will have members consisting of Windows user identities.
To set permissions, you can use SQL Server Management Studio. Under the Database | Roles folder, you can create roles, specify database permissions, assign membership to Windows user or group accounts, and then grant read or write permissions on specific objects. Typically, Read permissions on a cube are sufficient for client connections that use, but do not update, model data.
Check Configure HTTP Access to Analysis Services on IIS 8.0
Regards,
Zoe Hui
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