How to fix CA certificates issue on Debian 9
I had a Debian 8 VPS (OpenVZ) and it was working flawlessly. I am using mybb forum and it was able to send emails using 3rd party email service.
Then I moved my site to a new VPS running Debian 9 and ever since I am facing problem in sending emails. I suspect it has something to do with CA certificates because whenever I try to access any https based site using wget then I get error so I have to use "--no-check-certificate".
I don't know if it is due to Debian 9 or the problem is in how provider installed Debian 9 (I am Linux noob)
mybb is throwing following error message whenever it tries to send email.
When I use TLS to send email
Error: stream_socket_enable_crypto(): SSL operation failed with code 1. OpenSSL Error messages: error:1416F086ConfusedSL routines:tls_process_server_certificate:certificate verify failed
When I use SSL to send email
Error: fsockopen(): SSL operation failed with code 1. OpenSSL Error messages: error:1416F086ConfusedSL routines:tls_process_server_certificate:certificate verify failedError: fsockopen(): Failed to enable cryptoError: fsockopen(): unable to connect to ssl://smtp.zoho.com:465 (Unknown error)Error: stream_set_timeout() expects parameter 1 to be resource, boolean given