So if disabling security on the client side, they can connect fine. But whichever security option they choose, it is the same problem..
Edit: So I found if a user switch to Miranda client, they can connect without problems. In OpenFire console, it says they are connected via SSL.
I tried to edit the same settings in Psi so that they appear to be the same as in Miranda, but still no connection.
Maybe a problem with Psi?
Edit: Confirmed. Also when trying with IM+ Pro for mobile, users can connect without a problem. Connection is SSL. Seems to be an issue with OpenFire and Psi-client?