This week we had an issue with Outlook not sending emails to the server. We tried all the normal fixes repair, restart etc but no luck.
The next idea was to reinstall office 365 so a quick uninstall and there it was gone, a quick reboot to get rid of any registry keys that where hanging about.
The installer was downloaded from the Microsoft site and hung when trying to install. After a half dozen attempts it was time to talk to the might Google, and it came up with as file to completely remove office from the computer as it seems that some bits sometimes remain stopping the reinstalling.
Download the o15-ctrremove cab file, ran it and after a quick reboot was able to reinstall Office 365 No problem.
You can download it
Here or seach Google for a Copy
Here
Hope this helps you.