I have my zimbra login page: https://mail.mydomain.com

After I installed zimbra I could not login as admin. I created another admin account through the terminal.
I am now able to login to the admin page (with my new admin account) and created a couple of users:

test@mail.mydomain.com with password 123456
test2@mail.mydomain.com with password 123456

I used the default COS settings. Accounts are active.

I cannot login to these 2 accounts or the original admin account. The admin account appears to be ok and I reset the password, but still cannot login with that.

Something seems to be messed up. Or am I missing something simple? Any ideas?