Download the Putty here
1. Log in Yeastar S-Series IPPBX, go to Settings > System > Security > Service, enable SSH.
2.Enter the IP of Yeastar S-Series IPPBX and SSH port(default is 8022).
3.Then configure the putty with enough lines.
4.Login the SSH with username/password: support/iyeastar(or random password).
If the password is incorrect you need to login to the web and go to Settings > security > service to disable and enable SSH, then you can see the password pop up.
5.Then input the commands:
6. Make the test call or other tests relevant with your issue. Finally copy all of the logs and save them in a .txt file. And send us the log.