Microsoft to Deprecate Legacy TLS for Exchange Online
🔒 Microsoft will block legacy TLS connections for POP and IMAP access to Exchange Online starting July 2026, deprecating TLS 1.0 and TLS 1.1. Connections that attempt to use those versions will fail, which may prevent older email clients, devices, or embedded systems from connecting. The company says most customers won't be affected because the majority of traffic already uses TLS 1.2 or later. Administrators are advised to verify client configurations, update custom or legacy systems, and avoid legacy endpoints to prevent disruption.
