SharePoint 2013 - Workflow suspenso: HTTP 401 You do not have permission to perform this action or access this resource.

O fluxo de trabalho no SharePoint 2013 fica normalmente no estado suspenso com a mensagem de erro "You do not have permission to perform this action or access this resource." se o fluxo está configurado para enviar e-mail(s) e para iniciar automaticamente.

Mensagem de erro no interface:

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RequestorId: <GUID>. Details: An unhandled exception occurred during the execution of the workflow instance. Exception details: System.ApplicationException: HTTP 401 {"error":{"code":"-2147024891, System.UnauthorizedAccessException","message":{"lang":"en-US","value":"Access denied. You do not have permission to perform this action or access this resource."}}} {"Transfer-Encoding":["chunked"],"X-SharePointHealthScore":["0"],"SPRequestGuid":["<GUID>"],"request-id":["<GUID>"],"X-FRAME-OPTIONS":["SAMEORIGIN"],"MicrosoftSharePointTeamServices":["15.0.0.4675"],"X-Content-Type-Options":["nosniff"],"X-MS-InvokeApp":["1; RequireReadOnly"],"Cache-Control":["max-age=0, private"],"Date":["<DATE>"],"Set-Cookie":["WSS_KeepSessionAuthenticated={<GUID>}; path=\/"],"Server":["Microsoft-IIS\/7.5"],"WWW-Authenticate":["NTLM"],"X-AspNet-Version":["4.0.30319"],"X-Powered-By":["ASP.NET"]} at Microsoft.Activities.Hosting.Runtime.Subroutine.SubroutineChild.Execute(CodeActivityContext context) at System.Activities.CodeActivity.InternalExecute(ActivityInstance instance, ActivityExecutor executor, BookmarkManager bookmarkManager) at System.Activities.Runtime.ActivityExecutor.ExecuteActivityWorkItem.ExecuteBody(ActivityExecutor executor, BookmarkManager bookmarkManager, Location resultLocation)
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Mensagem de error no log do SharePoint:
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It’s app only request, but the app <identity> is not allowed to use app only policy.

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Solução: Ativar o feature “Workflows can use app permissions” na página OU desativar e ativar o feature novamente.

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