I have an application that exports an .xls file. I have a co-worker with Windows (10) pro and Office 365 ProPlus, when they run the application and execute the export, the file opens Excel 2013 and displays the data. I also have Windows (10) pro and Office 365 ProPlus, when I execute the export, Excel 2013 opens with a grey page. If I save the file, and then open Excel 2013 and then open the file, it opens in Protected mode with data. I went through the options pages and the check boxes compared between the (2) machines. I don't know what other feature to investigate.
I did a repair on the Office 365 and this fixed my issue.