Hello Stefan,
Thx for your answer.
No, i changed nothing.
Yes, i tried everything, reboot box, computer, reinstall the app server / client.
No firewall, no AV, tried an other computer / on an other phone.
When i launch the app, it's searching for 20 sec than error, credential are ok.
If you confirm that all is ok with the broker, i'll continue to search and if you have any tips i'll be happy.