The Office 365 suite of products from Microsoft uses a “rental” model rather than the traditional perpetual license model. Most versions of Office 365 include the full Office Desktop Suite, including Microsoft Word.


eXtyles works as a Word add-in to the Office Desktop Suite. eXtyles fully supports Office 365 when the version you have purchased includes the full Office Desktop Suite (e.g., Office 365 Business, Office 365 Business Premium, Office 365 Home) and you have installed the full Office Desktop Suite on a Windows laptop or desktop PC. eXtyles does not support mobile versions of Office 365 running on a tablet or smartphone.


Like other instances of Microsoft Office, Office 365 is available in both 32-bit and 64-bit versions. Starting in January 2019 64-bit Office 365 became the default install for Office 365. This has implications for eXtyles customers running Office 365 because while eXtyles can run on either 32-bit or 64-bit Windows, builds earlier than 5143 (December 19, 2022) are not compatible with 64-bit Office.


This means that if you are subscribed to Office 365 and you are using a build of eXtyles from before December 19, 2022, you may experience new compatibility problems with eXtyles if:

  • you are subscribed to automatic updates, and
  • you (or your IT department) have not explicitly selected the 32-bit option. 


For instructions on selecting which version to install, see this Microsoft Office Support article. Note that if you have updated to a 64-bit version of Office 365 and are using an eXtyles build from before December 19, 2022, you will need to uninstall that version in order to download and successfully install the 32-bit version.