Javier Guillen posted on March 30, 2011 09:53
If PowerPivot for Excel was working fine and all of the sudden it disappeared, try checking to see if the add-in got disabled (it has happened to me a few times and I’m still not quite sure why Excel disabled it)
Go to File -> Options -> Add-ins. Once there, Select COM Add-Ins and click ‘GO’
Once there, a window with open with the option to re-enable PowerPivot again
