You may receive the following error when running the PowerPivot Configuration Tool on a SharePoint application server running PowerPivot for SharePoint:
The user is not a farm administrator. Please address the validation failures and try again.
The user is required to be both a farm administrator and a site collection administrator in Central Administration.The error may occur if the user is not assigned to one of these groups.
To add the user as a farm administrator, go to Central Administration > Security > Manage the farm administrators group. Click on New > Add Users, enter the user, and click Share:
To add the user as a site collection administrator in Central Administration, go to Central Administration, click on the gear icon on the top right, and select Site settings. Then go to Users and Permissions > Site collection administrators. Enter the user and click OK:
After ensuring the user is in these two groups, the user should be able to run the PowerPivot Configuration Tool successfully.