Classic Outlook updates, features, fixes and known issues (mid-August 2026)

Classic Outlook received 3 security updates as part of Microsoft's record-breaking August 2026 release, which included 89 Office security updates. Highlights include a new issue causing missing Copilot buttons in Classic Outlook, an ongoing Shared Calendar invitation crash issue, a fix for encrypted email messages failing to open, and a reminder about the Semi-Annual Enterprise Channel servicing…