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Resolved Problem with smtp

python

Regular Pleskian
Since I update plesk to the latest version I can not send mails from smtp it tells me something like access denied. These are the errors I found:

Jul 6 21:21:03 server postfix/smtpd[1088]: connect from server.com[xx.xx.xx.xx]
Jul 6 21:21:03 server postfix/smtpd[1088]: SSL_accept error from server.com[xxxxxx]: 0
Jul 6 21:21:03 server postfix/smtpd[1088]: warning: TLS library problem: 1088:error:14094418:SSL routines:SSL3_READ_BYTES:tlsv1 alert unknown ca:s3_pkt.c:1275:SSL alert number 48:
Jul 6 21:21:03 server postfix/smtpd[1088]: lost connection after STARTTLS from server.com[xxxxxx]
Jul 6 21:21:03 server postfix/smtpd[1088]: disconnect from server.com[xxxxx]

I try to connect with openssl from ssh:
openssl s_client -starttls smtp -crlf -connect server.com:587

Returns this error:


CONNECTED(00000003)
depth=0 C = CH, L = Schaffhausen, O = Plesk, CN = Plesk, emailAddress = [email protected]
verify error:num=18:self signed certificate
verify return:1
depth=0 C = CH, L = Schaffhausen, O = Plesk, CN = Plesk, emailAddress = [email protected]
verify return:1
 
Last edited:
Hi python,

as you can see, you use the default SELF-SIGNED certificate from Plesk for your secure connection. Pls. consider to replace the certificate with a valid one, if you desire secure connections. It's realy easy now with Plesk Onyx and Let's Encrypt to create a valid certificate for "mail.YOUR-DOMAIN.COM" over your domain - specific settings and it is again very easy to secure your mail - server with such a certificate ( => HOME > Tools & Settings > SSL/TLS Certificates ):

Plesk-Onyx_Tools-Settings_SSL-TLS-Settings_001.png
 
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