title: Excel Add-In only works when doing a disable and enable
body: <p>We are using a 3rd party Add-In in Excel which for some reason does not work on my machine but on everyone else's. The weird thing is that when you disable and enable the add-in, it starts working and the tab shows on top. But if you save the doc and reopen it, the tab is gone again and the links it is supposed to update does not work again.</p>
  
  <p>Not sure if it's the particular add-in, but let me name it in any case, it's called 'Historian Client Workbook'.</p>
  
  <p>I'm using Excel 2013.</p>