Does not seem to have a working outgoing internet connection.

The first time I installed bimserverwar-1.5.125.war on our local server (Windows Server 2016) with Tomcat 8.5, It went well, with Windows Firewall on and IE Enhanced Security Configuration on.
Then after I cleared old files, directories and logs and tried to reinstall the same pack, "Your BIMserver does not seem to have a working outgoing internet connection." when Windows Firewall was off and IE Enhanced Security Configuration was off.
Ping to local getaway, Intranet and Internet are working.
Is it because of IPv6 connectivity? The IPv6 connectivity shows "no network access".
I tried to configure again today and it works. Again I have IPv4 Internet access but no IPv6 network access.
I guess the "no Internet connection" problem does not occur at my side, rather it occurs at the side storing those plugins. Can you have some "Retry" button on the setup page rather than letting me setup a BIMserver even without console which I have no way to install them and have to start over again.
Retry button will be considered.
Is it related to the code BIMserver/blob/master/BimServer/src/org/bimserver/webservices/impl/ServiceImpl.java#L3033? Why do we need to check whether we can visit www.google.com?