we are receiving a lot of complaints about unavailable services. In detail the What’s new? tab in the client, downloads from our content servers (maps, mods, replays, etc.) are broken for all users using IPv6.
We are aware of this issue and sorry for the inconvenience. While fixing the server setup might take a while, a confirmed workaround is deactivating IPv6 on your computer. Our fellow contributers have created a walkthrough how to do that on Windows 10 in our wiki here (use on your own risk).