Which edition of Excel 2013 are you using? The supported editions of Office supported by the SQL Server 2012 SP1 Data Mining Add-ins for Microsoft Office are as follows:
- Professional Plus
Besides, make sure the cube is hosted in a SSAS 2012 instance.
TechNet Community Support
There is no team at Microsoft that is actively working on the data mining add-ins.
People who worked on the data mining add-ins have moved to Predixion Software and continue development there.
I recommend that you install add-ins from Predixion (https://www.predixionsoftware.com/)
Predixion supports all the latest versions of OS, SQL and Office and has a dedicated support team should you have any questions or run into issues.
Tatyana Yakushev [PredixionSoftware.com]