Since installing DTTG 3.0.5 yesterday, I have been unable to sync my iPad to my laptop. The sync worked fine and mostly flawlessly prior to the update.
Both the iPad and the laptop are on the same wifi network (my home network); neither is running a VPN; Each attempt to sync databases results in a “Starting synchronization” status (via a long press on the sync icon) followed eventually by a “Connection to server timed out” error log message on both devices. Interestingly, those same messages appeared even when I restarted the iPad, turned off its Wifi and Bluetooth, connected the iPad directly to the laptop with a USB cable (i.e., not via a hub), launched DTTG and tried to sync.
Prior to those timeouts, I received a raft of preview-could-not-be-created messages, like those described in this thread.
BTW, the iPad is running iPadOS 14.4.2, and the laptop is running DT 3.6.3 on macOS 10.15.7. And even fully loaded with the databases I’m trying to sync, the iPad has more than 700GB of free space, and the laptop has more than 2.5TB free. In other words, I don’t think space is an issue.
edit: I should also add that only the laptop is designated as the server accepting connections. The iPad has never been set up to accept connections.