This is not related to an update, most likely is your firewall blocking Diving Log from syncing (which may be caused by the update). Make sure to allow the Diving Log application to access the network in your firewall settings. Please see here for additional tips and tricks:
No, reinstallation won't change anything. Which firewall do you use? Try also to restart your WiFi router by unplugging it from the power for 1 minute.
I found the solution. AVG is blokking the communication. I do not have the AVG firewall however. Maybe some other protection which is included. Switching off AVG completely solved the problem.