This applies to Windows systems.
The problem is, that the permissions are not always renewed for the user directly. For instance, with my own user, I had to log off and logon to have the correct permissions on this file share.
The same applies for the Bridge user, that runs the services. Unfortunately, the restart of the service (bridgeserver.exe process) is not sufficient. You have to restart the Windows service “E2E Console”. This requires a short maintenance window as you have to stop all services prior to restarting the Windows service. But it does the job.