Tabular not starting when double click on a workbook – Excel 2016

With certain versions of Excel 2016 when double click on a Tabular workbook add -in will not start and all the buttons in the Tabular ribbon will be disabled, but when open Excel first and then from its menu go File->Open and open a Tabular workbook the add in will load as expected and the log -in screen will show. To fix the issue you need to upgrade your Excel version to the latest one available.