Cannot create new account, with the signup button, on the realm client

The signup button takes you to "https://secure.realmserver.com/cgi-bin/subscribe.exe" and you get "This site can’t be reached"

However you can create an account on the "https://realmserver.com/restricted/realm_accounts" page, just fine.

Yeah this is on the Known Issues list from the 4/20 dev update in the announcement forum. It's potentially not the only broken in-game link!

I can't get in, keep getting : Invalid login name or password. Please re-enter your login name and password to continue.

You need to create two accounts, one for this website and the other one for the realm server, link at the top of this page, go to Account/GameAccounts/Create New Account. Use the realm server login and password on the realm client.