I logged on today, got my new items and that was fine.
Then I joined my friend in the guild hall THROUGH THE FRIENDS TAB "JOIN KNIGHT OPTION," and I was able to access the guild hall.
However, I later tried to enter the guild hall through the garrison part of Haven. Immediately something popped up saying something like "do you want to enter your guidhall?" and a giant option saying "enter guildhall" like the "start" option in the mission menu. However, before I could click "join" the spiral knights window closed.
I tried to run sk again (and again), it loaded, and I went immediately to the garrison (just like if you were accidentally disconnected and you ran SK again), the menu popped up asking if I wanted to access my guildhall, and the sk window closed again.
I don't know if I am the only person experiencing this (as I may not have downloaded a file or something).

In game name: Abosolute.
Something to note is that I run SK through armorgames.com.

Edit: The option of entering the guildhall through the ready room works.
Edit: I refreshed the page, and ran SK again, which allowed me to enter the guildhall. However, that wasn't the root of the problem. I tried to enter the guildhall with my account "Sketman" which doesn't use armorgames and the error mentioned above occured. I saw a menu pop-up and the SK window was closed.