Whether you deploy your TFs service in the workgroup mode or in the domain mode, you will encounter this situation. Generally, we create a special user group as a project team, such as projectteam1. Then, we add users to this group, and then add the group to a permission group in TFs, in this way, we can minimize the workload of configuring permissions in TFs, but you will find that when you create a new user, you also add the project team, TFS takes a very long time to get this update. That is to say, your users need to wait (4 hours, according to TFs Team). This situation is intolerable.
Therefore, the quickest way is to use iisreset to restart the Web service on your TFS, which forces all TFs services to restart and refresh the cache; your users can use TFs directly.
However, we hope to have a better method, such as adding a refresh function to the team resource manager or tfswa.