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Microsoft recommends migrating existing Azure DevOps OAuth apps to Microsoft Entra ID OAuth as soon as possible rather than waiting for the final cutoff date. All new integrations should use Entra ID OAuth.
The most precise public milestones currently available are:
April 23, 2025: Azure DevOps OAuth stopped accepting new app registrations. Existing apps can continue for now.
Existing Azure DevOps OAuth apps are stated to continue working until the platform’s official retirement in 2026, but no public month/day is listed in the docs/release notes.
Microsoft has already started preparation steps, such as regularly removing OAuth apps whose secrets expired more than 180 days ago.