Running as Administrator didnt help, but turning off UAC did.
Weirdly even though I only turned off UAC on the server, the problem is gone on both the Local Client on the Server and the Remote Client on my Desktop. ANy idea why that is? We generally prefer to leave UAC on where possible. I've never heard of UAC affecting a windows service, and I assume it's the VCron windows service that writes to the config file?