Reinstall Microsoft Office from 64 bit to 32 bit

A support of the 64-bit Office variant is not possible since Microsoft does not allow any extensions in the scope of TAPICall. Microsoft itself recommends Office 32-Bit to use Add-Ins and makes it clear that there is no difference in performance, except when using 2GB Excel-Tables: https://office.microsoft.com/de-de/auswahlen-der-32-bit-oder-64-bit-version-von-office-HA102840825.aspx
Uninstall the existing Office 64-Bit, then you can install the 32-Bit version. You do not have to make any further settings or back up your E-Mails. These data are not changed during the uninstallation and automatically integrated into the 32-bit version. The process does not take 5 minutes (vgl. Video).