Problem:

When deploying the “JsonADDomainExtension” on an Azure virtual machine, you receive the following error: “userExists”

Solution:

Either specify the correct OU for the existing object in AD or delete the object from AD and redeploy.

Explanation:

When domain joining an Azure virtual machine using the “JsonADDomainExtension”, if the object has previously been added to AD then the object must be re-joined using the same OU path. If a new OU path is desired, the old AD object must be deleted before deployment.