The warband bank seems to be sort of working now but when I open it on characters on my second wow account they get the screen to buy a slot (they can’t see what’s already in the slot that was already purchased) - when i try to buy a slot it says “you can’t buy any more slots”.
" Also, similar to pet battles, players who play multiple characters simultaneously on multiple World of Warcraft accounts will find that only the character that logs into the realm first will have access to the Warband Bank."
In my point of view anyway, the biggest problem here is that the warbank gets locked to the first wow account that logged in.
I do understand the complexity in coding required to be able to guaranteed security enough to allow multiple accounts accessing, that really isn’t something simple to do, BUT it is very simply to allow the player to choose which account has the warbank access, that is easily doable.
by instead of locking the warbank during log in:
1)lock it only when the first access attempt happens
2)allow unlock from the account without logging off
or
3) allow the player to force having access in the current account and disabling access in the other accounts.
This could be done with either a button near the bags or option in the character picture
Just to follow up I figured out that if i log out and login on the char that can’t access (due to what other replies have mentioned) I can access it. Not ideal and makes me a little reluctant to deposit a lot of gold into the warbank.