One problem I have run into a few times is the time being off on ShoreTel phones. This has happened with new installs and systems that have been running for a long time. After checking to make sure that the phones were getting a SNTP address from the network, and that the address was set to the ShoreTel server, I found that the NTP service was not started on the ShoreWare director server. It was set to manual for some reason. So if you go in and set it to automatic and start the service a few minutes later the phones should show the correct time. See below, make sure you have it set to automatic.