Applied on Windows 7.
Office 2013 online streaming installation stopped at 84%, after couple of hours struggling to find a solution, that worked for me:
1) Logged on with an admin account
2) Uninstalled office from the programs and features
3) Ran office 2013 cleanup utility ( fix it ) from here http://support.microsoft.com/kb/2739501
4) Rebooted the machine.
5) Deleted manually C:\program files\microsoft office & C:\users\%username%\AppData\Local\Microsoft\Office & C:\users\%username%\AppData\Local\Temp
6) Stopped all the antivirus and firewall services.
7) Ran the Office installation again successfully!