Entra Connect Sync: upgrade to 2.6.84.0 or later and use application-based authentication

Entra IDActive Directory

Who is affected

Every organisation running Microsoft Entra Connect Sync. Synchronisation stops after this date on servers that have not been upgraded and switched to application-based authentication.

What to do

1. Check the installed Entra Connect Sync version on every sync server, including staging servers.
2. Download the current build from the Microsoft Entra admin center and upgrade.
3. Configure application-based authentication and confirm .NET Framework 4.7.2 and TLS 1.2 are in place.

Source

“Mandatory upgrade required: Upgrade Microsoft Entra Connect Sync to version 2.6.84.0 or later and configure application-based authentication by April 7, 2027.”

Checked 9 Nov 2026 Link to this deadline