This is some feedback from another user, who also had problems after upgrading:
What worked was:

* uninstall all Office software (all versions)
* delete normal.dotm template to be sure it was clean
* clean the GAC of Office assemblies
* run registry cleaner in case of remaining cruft
* install VS Tools for Office 2010
https://www.microsoft.com/en-us/download/details.aspx?id=48217