FileNotFoundException with Microsoft.AnalysisServices.Xmla

I ran across two cases that were hitting the following Exception within SharePoint trying to run the PowerPivot Management Portal. This was located in the SharePoint ULS Log:

EXCEPTION: System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.AnalysisServices.Xmla, Version=11.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91' or one of its dependencies. The system cannot find the file specified. File name: 'Microsoft.AnalysisServices.Xmla, Version=11.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91' at Microsoft.AnalysisServices.SharePoint.Integration.Redirector.WCFTransport.Init() at Microsoft.AnalysisServices.SharePoint.Integration.Redirector.WCFTransport.Connect(String dataSource, String applicationName, String& errorMsg)

The environment was setup in a similar way to the following - 3 SharePoint Services consisting on one WFE and two App Servers.

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