PPS – SharePoint URL is a valid site but …
I received this error today when launching Performance Point Server (PPS) Designer for the first time.
The SharePoint URL is a valid site but PerformancePoint Services features have not been configured. Please contact your site collection administrator for assistance.
Turns out there is a feature “PerformancePoint Services Site Collection Features” you must first activate. After that everything works great and connected! 
add the same user in sharepoint designer group.it will work.