I'm having an issue with .xlsx files created with Excel Web App. 

Something or someone messed (probably my kid :-P) file association, because excel files opens with LibreOffice's Calc, while I want them to be opened with ModernUI IE11. I've tried to set IE11 as default application, but it only displays a blank page.

When I'm login directly to SkyDrive service with IE11 it's working fine. 

Well that's all.

Thanks in advance.