This is a good article if you’ve updated to Excel 2013 and want to update your PowerPivot models.

Start PowerPivot in Excel 2013 add-in

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PowerPivot in Excel 2013 is an add-in you can use to perform powerful data analysis in Excel 2013. The add-in is available in Microsoft Office Professional Plus. It’s built-into Excel 2013 but is not enabled. Here’s how you enable PowerPivot before you use it for the first time.

  1. Go to File > Options > Add-Ins.
  2. In the Manage box, click COM Add-ins> Go.
  3. Check the Microsoft Office PowerPivot for Excel 2013 box, and then click OK. If you have other versions of the PowerPivot add-in installed, those versions are also listed in the COM Add-ins list. Be sure to select the PowerPivot add-in for Excel 2013.

Start PowerPivot in Excel 2013 add-in - Excel - Office.com

Cross Posted from Dan Fay's Blog (http://blogs.msdn.com/dan_fay)