Please go to the folder: C:\Program Files\Common Files\Microsoft Shared\VSTO\10.0
Delete these files: VSTOInstaller.config (ggf. auch VSTOInstaller und VSTOInstaller.config.exe)
Download Visual Studio 2010 Tools from Microsoft Site and Install it Visual Studio 2010 Tools for Office Runtime: https://www.microsoft.com/en-us/download/details.aspx?id=48217
After this try to re-install it.