The following link has the information to configure SSAS:
The following are the general information regarding SSAS configuration:
a. Navigate to the corresponding Application pool at IIS and check whether it has right authentication or not.
(i) Click Application pool and follow the link “Set Application Pool Defaults” present in the right tree view.
(ii) Navigate to the Identity tab present under Process Model tree.
(iii) Choose your SSAS account type whether predefined or configured for specific user (In this scenario we have chosen “Local System” under Built-in account).
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