AppVeyor uses OAuth to access Azure DevOps resources. Azure DevOps removed obsolete authorization scopes from OAuth flow which broke the integration with AppVeyor. As a result some AppVeyor customers were unable to login with VSTS button or start new builds with VSTS repositories.
We deployed a fix and the customers should be able to re-authorize Azure DevOps on either “New project” or “Account > Authorization” pages. Unfortunately, we were unable to keep original OAuth app registration and had to create a new one, because scopes of existing app registration cannot be updated.
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