Microsoft will block legacy authentication methods by default in Microsoft 365 starting mid-July 2025 through August as part of its Secure Future Initiative. The notification, MC1097272, emphasizes the need for organizations to adapt their systems due to the vulnerabilities of legacy protocols, such as the Remote PowerShell (RPS) protocol for SharePoint and OneDrive, and the FrontPage Remote Procedure Call (RPC) protocol. Additionally, Microsoft will require administrator consent for third-party applications accessing organizational files and sites, shifting the responsibility from users to administrators to enhance security. These changes will apply universally across all Microsoft 365 tenants.