Why is the server constanly down ? Does anybody know ?
It's mostly up 24/7, but as soon as one server gets ddos'ed they all enter the protective mode, which disables foreign IP connections for some time.
I encounter this problem really often since I'm located in UK, strangely enough it also applies to the teamspeak server.
Edit: you can try using a VPN located in Latvia, not sure if that'd help or is even allowed. 
yeah its annoying, but i still dont understand if the ddos attack is vs kick or vs the provider?
but i realized when DD2, GG, CSDM and War3-Servers are down or attacked, the ZM+War3 server stays available for foreign IPs (yesterday i saw first time, it was 20 min off or so)
so if you are bored when the other servers are offline, come n kill some zombies to get prepared when corona-zombies try to take over 
edit: it feels like, since i said about the ZM-server its also affected more often ://
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