vsto add ins

The vsto add ins tag covers guidance for organizations running Microsoft 365 Apps with 32-bit Office and dependent COM or VSTO add-ins. Current coverage explains that Version 2606 does not force a migration to 64-bit Office, so the update should not be blocked solely because these add-ins are in use. Instead, Microsoft recommends representative compatibility testing before deployment to add-in-dependent devices. Higher-risk systems may remain on Version 2508 while testing continues, but only through September 8, 2026. The discussion also distinguishes Microsoft 365 Apps channel unification, which changes feature delivery frequency, from the architecture of the installed Office applications.