OpenVPN error under Android?

Question

Android

Good day to all.
I set up OpenVPN according to this article
. I generated a configuration with the .ovpn extension, imported this configuration in the application on my smartphone, but when I try to connect to the servers, I get the following error:

OpenVPN core error: PolarSSL: cert certificate is undefined

Google did not help to deal with this problem, since selenium is not in English.
Help solve this problem.
Thanks in advance

Answer 1

Well, in article it is told about certificates.
You have not selected a certificate on the client device