I was hoping to find an answer to my issue in this article but when adding multiple content types I run into a couple of issues. It works fine for .dotx templates, so I tried the same with an Excel and a PowerPoint template, but to no avail, I guess they don't like the "Document" parent type, or I must be missing some other point.
Firefox throws a "'New Document' requires a Microsoft SharePoint Foundation-compatible application and web browser." Why does it work with Word but not with Excel & Powerpoint?
Other browsers (Chrome, IE11, Edge) work to some extent. With PowerPoint custom content type: - clicking New on a Library WebPart opens Powerpoint, attempts to authenticate to the domain and then says it can't connect. - clicking New on the Library page itself creates a new file "POTX File.potx" based on the template in the library, but you have to open it manually.
With Excel custom content type: - clicking New while Excel is already running on your PC creates a new book1.xlsx based on the template. - clicking New when Excel is not running opens Excel but doesn't load the template.
Does somebody have some insight on this? Thanks!