Recently in our tenant appeared a new employeeId attribute to the user entity.
We have over 40k user accounts; some of them created as pure Azure AD Users and others as Mail Users (via Exchange Online).
For many accounts, attempting to POST to the employeeId fails with the following error:
Unable to update the specified properties for objects that have originated within an external service.
We have tried with Microsoft Graph (/Beta), Azure Graph API (v1.6) and via the AAD v2 PowerShell module.
Could you please post this question in Stack Overflow and tag your question with microsoft-graph? This repository a good forum for receiving technical support on the API itself.
This forum is specifically for errors/issues with the Microsoft Graph Documentation set rather than the API itself. While there is certainly overlap, questions regarding the use of Microsoft should be posted on Stack Overflow where you'll likely get a quicker response and benefit other developers facing the same challenges.
Posted in Stack Overflow - EmployeeId Not Working
Added missing employeeId property to beta documentation: https://github.com/microsoftgraph/microsoft-graph-docs/pull/1961
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Added missing employeeId property to beta documentation: https://github.com/microsoftgraph/microsoft-graph-docs/pull/1961