Symptoms
Assume that you have configured Microsoft SQL Server 2012 or SQL Server 2014 PowerPivot for SharePoint 2013 by using PowerPivot for SharePoint 2013 Configuration Tool. When you retract and redeploy PowerPivotFarmSolution.wsp from SharePoint 2013 Central Admin, the solution is deployed to "C:\Program Files\Common Files\Microsoft Shared\Web Server Extension\14" folder instead of the "C:\Program Files\Common Files\Microsoft Shared\Web Server Extension\15" folder.
Resolution
The issue was first fixed in the following cumulative update of SQL Server.
Cumulative Update 3 for SQL Server 2014 /en-us/help/2984923
Cumulative Update 1 for SQL Server 2012 SP2 /en-us/help/2976982
Cumulative Update 10 for SQL Server 2012 SP1 /en-us/help/2954099
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
Workaround
To work around this issue, redeploy the farm solution by using PowerPivot for SharePoint 2013 Configuration Tool.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
