I have the Office 365 Professional Plus edition. I'm confident of this, as I cancelled my 365 Home Edition today and registered the Professional Plus account just to be able to use PowerPivot. 

I have tried the following KB article: http://blogs.technet.com/b/the_microsoft_excel_support_team_blog/archive/2013/10/16/excel-2013-power-pivot-or-powerview-add-ins-are-not-in-com-dialog.aspx.

There is no registry entry for PowerPivot, just PowerView. I've tried deleting the PowerView key with no success.

I have reinstalled and installed following this Microsoft KB article: http://support.microsoft.com/kb/2739501/en-us.

I've used both the "Let me fix it" and the manual techniques with no success. I have uninstalled and reinstalled a total of three times, the last in "Clean Boot Mode."

I have looked for updates for Excel. The latest one from 6/30/2014 will not install "because there are no programs affected by the update."

As suggested on other posts, I have attempted a full repair.

This is incredibly frustrating. 

Any ideas?

Adam

I just attempted to uninstall and reinstall again, this time with the ProPlus trial executable. I got stuck in a "Office 2013 Configuration has encountered a problem" loop. Uninstalling once again.

Adam

Hi Adam, 

Did you ever figure out how to remedy this issue? I tried the exact steps you did and absolutely could not figure it out.