On a 64bit Win7 pc, with 32bit O365. My account is fine as it works on other pc and also android.  No change after reinstall, repair, etc.

Splash screen "Starting...", never opens, that's it

The dots keep scrolling across, and never proceeds to the login screen:

Also tried to unplug all usb, except mouse

It does not crash, it just never starts. 

From O365 support link, I ran the Fix-it and then deleted the folder as instructed.

Search for lync.exe in C:\Program Files (x86)\Microsoft Office\Office15 and shift right click --> run as different user, enter admin credentials.

If you are able to login, try to disable third party apps or reinstall .netframework as well as skype for business/client.

I have the same problem, on windows 8 \MS office 2015. Did you get it solved? If so what was the solution?