Unless you uninstalled Office 2010 before installing Office 365, you may only have compounded the problem. If you didn't uninstall Office 365, then use the Office 2010 uninstaller at https://support.microsoft.com/en-us/kb/971179 to make sure that's completely uninstalled, then reinstall Office 2010 or Office 365 (you can't install both, as Office 365 isn't compatible with a standalone edition such as Office 2010).

If that doesn't resolve your problems, there may be more fundamental problems with your Win 10 upgrade, in which case, see:
http://answers.microsoft.com/en-us/i...7-f40096ec3085
http://www.tenforums.com/tutorials/1...e-upgrade.html

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]