I spent a portion of the last two weekends attempting to upgrade my homelab vCenter Server running on Server 2016 from 6.5.0 to 6.5.0-U1 with little success. My implementation is only a month old and non-complex, aside from the external Platform Service Controller servicing the single vCenter Server (so far).
Both the PSC and the VCS returned the same error during installation: “Installation of component VCSServiceManager failed with error code ‘1603’. Check the logs for more details.”