Microsoft to Block TLS 1.0 and 1.1 for Exchange Online POP and IMAP in July 2026
Summary
Microsoft will block TLS 1.0 and 1.1 for POP3 and IMAP4 connections to Exchange Online starting in July 2026. Legacy devices and applications must support TLS 1.2 or later to avoid connection failures.
Key points
- Exchange Online POP3 and IMAP4 connections will require TLS 1.2 or later starting in July 2026.
- Connections using TLS 1.0 or TLS 1.1 will fail after support is removed.
- Microsoft says most current POP and IMAP traffic already uses TLS 1.2 or later.
- Legacy devices, embedded systems, and custom applications may need updates.
- Microsoft advises customers to check client configurations and confirm TLS support with application or device vendors.
Article Details
- Event Type
- Planned deprecation of TLS 1.0 and TLS 1.1 for POP3 and IMAP4 connections to Exchange Online, beginning in July 2026.
- Impact
- Connections using TLS 1.0 or TLS 1.1 will fail, potentially disrupting legacy devices, embedded systems, and custom applications unless updated to support TLS 1.2 or later. Microsoft says most users are unlikely to be affected because most POP and IMAP traffic already uses TLS 1.2 or higher.